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FAQs on Marine Water Quality involving Natural Nitrate Reduction, helping some Anaerobic Bacteria

Related Articles: Nitrates in Marine Aquariums, NitritesAmmonia, Establishing Cycling, BioFiltrationPhosphate, SilicatesNutrient Control and ExportDeep Sand Beds

Related FAQs: Denitrification/Denitrifiers, Nitrates 1, Nitrates 2, Nitrates 3, Nitrates 4, Nitrates 5, Nitrates 6, Nitrates 7, Nitrates 8, Nitrates 9, Nitrates 10, Nitrates 11,  & FAQs on: The Actual Science Re: NO3 Compounds, Importance, Measuring, Sources, Means to reduce: Algae, Other Biota, Physical Filters, Chemical Filters... NitritesAmmonia, Phosphate, Silicates, Biological Filtration, Fluidized Beds, Denitrification/Denitrifiers, Bio-Balls, Wet-Dry Filters, R.O./Distilled/Treated Water Chemical Filtrants Deep Sand Beds

NNR Short List: Anaerobic media... (Live Rock, Live Sand, Siporax Beads et al., Ceramics like Eheim's Ehfi-Mech), DSB, Plenums, Refugiums... possibly a purposeful denitrator... commercial or DIY

QUESTIONS; Re NO3 accumulation       11/13/13
Hello Mr. Fenner,
I have some questions that I hope you can advise me. This is my equipments:
1.       210 gallon reef with 3  250W (MH 20K) and 4 PCs (96W each).
2.       29 gallon refugium with two T5s (24W each)
3.       20 gallon sump.

4.       Octopus skimmer rated for 250 gallon.
5.       7 power heads.
6.       Two pumps rated at 2100 GPH.
I recently had a huge nitrate spike (90+) (due to a canister filter that I did away since then) and changed water to get down to 40. I emailed you last week about doing another huge water change but you advised me to wait for the Nitrate to stabilize. Last night I did the test and now it is up to 70!
So these are my questions:
1.       How do I about changing water to get nitrate to acceptable level?
<Will cost a bunch of money and time to just change the water to dilute...
That is, this is NOT the route I would take; there are other methods...
Please read here re: http://www.wetwebmedia.com/nitratesmar.htm
and the linked files above>
 In the past I was consistently at 10.  Can I do 80 gallons every day for three days?
<You can, could, but again, this is not the route I'd go... Won't solve the ongoing NO3 accumulation issue... YOU SHOULD search, investigate re the source/s here... SOLVE them, add more purposeful denitrification, users of Nitrate... perhaps chemical filtrants>
2.       I have lots of fuzzy pink cotton balls in my refugium. They weighted my cheatos down so how do I combat this? Increase lights or flow in the refugium?
<Worth trying both>
3.       My corals are NOT thriving. Even the hardly GSP barely open. I threw away all my toad stools but the problem still existed. Likely due to high nitrate?
<... Likely the high nitrate is reflective of overall TOO MUCH metabolite period; and this is an issue>
4.       Do I have the right stuff for acceptable coral growth?
<... "Right stuff?"... the system, lighting is likely fine; but the overall filtration is wanting... too much nutrient being poured in, insufficient users, removal, cycling mechanism/s...>
I look forward to your reply. Thank you very much! Dai
<DO the reading Dai... consider your possibilities. Just changing water won't do it. Bob Fenner>
Re: QUESTIONS      11/13/13

Thank you for your reply. In the meantime, can I do 10% a day to get nitrate to 20?
<If you'd like; sure>
 Of course I will cut feeding way back too.
<Also a good idea>
 I use to give
a Nori sheet a day. Dai
<Do you have much fine substrate in the tank, 'fuge, sump? I'd increase all to about 4 in./10 cm. depth. BobF>
RE: QUESTIONS,NO3 control       11/13/13
I do not have any at all in the refugium. But I will place a 4 inch live sand this weekend.
<Ahh! This will help... in a few weeks, you should see a great drop in [NO3].
 I will do a video and let you see my set up. Dai
<I thank you. BobF>
RE: QUESTIONS       11/13/13

I forgot to tell you that I have sand in my main tank along with live rocks. You will see on my video. Dai
<Real good. B>

Re: Nitrate Reduction... f' also Lg. sys. maint., Shark sys....     9/15/13
... Are you joking? Re file size? Deleted. READ re our requirements, limitations... re-size and re-send all. B
Re: Nitrate Reduction    9/15/13

Ok,  Still working on the nitrate problem.   I have attached some pics of the sump and tank so you can see what I am working with.
<Have gone over all>
 I am looking at a few possibilities regarding this nitrate issue.   After reviewing the responses you have given me I am noticing I am very limited on what I can do.  Let me know what you think.    I have tried to figure a way to retrofit the bags but I have no way of setting them under the outflow pumps.   The sump was designed with an access tray that I was going to try to remove but could not I may be able to clip them to where the tray slides out by doubt it would be very effective.
<Do see CPR's site re:
  I do not have enough room in the sump for a refugium but I am going to have one built that I can tie into the main sump. 
Regarding that how many gallons does that sump need to be in order to be effective.
<As big as possible... whatever the largest size you can fit>
  In the meantime I have thought about pulling the matrix from the tank and cleaning it then placing it back into the sump.
  Would you recommend this or would this be more detrimental.
<Don't think it would make any difference at all; the washing... I'd just leave in place>
   I have noticed any heavy shifting can cause a nitrate and nitrite spike in my tank in the past.
<Shifting? Of what? How?>
  I have also noticed that since I have gone to changing the pads everyday that it almost seems pre mature since they look brand new when I pull the three floss pads out.  No staining at all.  Will an increase in water amount that I change per water change help to solve this problem. 
<Not much; no; and only temporarily... several hours to a day or so>
Possibly going from 100-150 gallons up to 200 gallons per week or even more or would that damage the stability of the tank.  
 I attached the pics so you can see the tank.  Everything is extremely healthy even the Duncans,  Mushroom Corals, Gorgonians and African Red Seastar.
  Maybe I am  over reacting but I just want to provide the best environment that I can for these guys.  PS.  I am using an API nitrate test kit and I have heard these test really high.
<I'd invest in a better make... API is really rudimentary... see WWM re such>
  I have three different test kits with API and have used all of them and they are all the same.  From your experience are these not accurate.
<Nor precise. Do get going on that 'fuge... add as much (a foot or more) of very fine sand... and alternating light cycle (RDP)... You're going to need all this, these changes, addenda as these fishes grow MUCH larger. Cheers, Bob Fenner>

Re: Nitrate Reduction    9/15/13
So to refresh
1.  Eliminate SeaChem matrix all together.
<Mmm, I'd keep it if I'd paid for it>
2.  Build as big a refugium as possible.
3.  Sand in refugium at a depth of one foot.
<Or deeper!>
4.  Increase weekly water changes to 200 gallons weekly.
<If you don't go broke or break your back!>
Is this accurate.
I assume you mean a one foot depth sand bed in the refugium.
<Ah yes. BobF>

Re: Nitrate Reduction; Shark Sys.      9/26/13
Leader of all that which is aquatic,
      Two things I thought of over the last few days that I would like your help on.
I have been thinking of adding a few more inches to the sand bed in the display tank.   Do you think this is a good idea with the sharks being large fish.
 <Yes I do>
Also.   I was wondering about adding a giant kelp plant
<... what species? Not temperate I hope/trust>
 into each of the four corners of my tank.  For two reasons.  I would assume the tangs could eat it but not faster than it would grow.  And it could be a very good looking addition to the interior of the tank and consume nitrates.
<Mmm, no... >
   The problem is I can not find any info of anyone keeping them in home aquariums and I cant find anyone that sells it.    Can you give me any info on either of these issues, it would be greatly appreciated.
<... the large brown (Phaeophyte) and red (Rhodophyte) algae that are kelps won't help here... Need to grow them, perhaps in a tumble culture in a separate sump/refugium... Have you been reading? B>
Shea B
Fw: Nitrate Reduction     9/26/13

Sorry I used the term Giant kelp.   Mainly a form of kelp with that look but smaller size.  Not sure if there even is one. Just so there is no confusion.  Sorry.
<No worries; there are many species... mostly too cold-water for your use... Do keep reading. B>

Substrate depth, SW, NO3, rdg.     9/12/13
Morning crew
I have been fighting the nitrate battle for a number of months now and have utilized a number of methods in effort to control (Vodka being the most effective however have recently taken this offline and am trying the Aquaripure).
<Have you read here?:
and the linked files above?
 I recently ran into a fellow enthusiast who ran nothing on this tank other than a protein skimmer and a couple of power heads and his water was pristine. His thoughts to me was that my 3" deep aragonite bed is the primary cause of the high nitrate issues and that I should reduce the entire bed down to approx. 3/4".
<A possibility... See WWM re substrate depth for marine systems... There are several references to this situation>
 If this is what I should do, is there any way that I can save all of the narcissus snails that are in it along with the smaller starfish that come out at night.
<You could "hand sift" much of the aragonite, saving many of these animals.
Another possibility is simply to add more fine material amongst the aragonite. READ here:
Scroll down to Mar. Substrates...>
 I have had the aragonite in my tank for almost 2.5 years so it's undoubtedly time to do something. I just want to make sure that what I do will be the most effective in the long term.
Let me know..thx Chris
<Read on! Bob Fenner>

High nitrate reduction... but so quickly??/Nitrate Control/DSBs 12/13/11
Dear Crew,
  Once again I must beseech you for help with an anomaly that I have experienced. About 3 weeks ago I added an 8" DSB into a 15"x15" section of my sump to help battle high nitrates. On Friday evening I did a test and got a reading of about 40ppm. I wanted to get that resolved, but it was later on and the children needed tending to, so I resolved to doing it first thing Saturday morning. I wanted to verify my reading so Saturday I did the test again and got about the same results. Unfortunately I got called away for some family stuff, and was never able to get my water change done for the rest of the weekend. Today I went to check the readings again, as I was somewhat worried as to what they  would be, but they read about 5ppm?!? I rinsed the tube out and rechecked two more times, and go the same result each time. I only had the one test kit (API) and so I couldn't verify it against another test kit to make sure it was reading right. The only other major change I made to the system was finally getting to hang my 2x250w metal halides (Yah scratch and dent LumenMax reflectors for $40), and removing the glass tops, replacing them with fluorescent egg crate diffusers.
I have them hanging 24" above the tank right now, as I went from 4x39w T5s.so it was just a little bit of a difference. But I am sure the coral appreciated it. Hehe. Everything in the tank has been reacting just fine to the light change, except some mushroom corals on the top of the tank that needed some shade. Sorry, got a bit off topic there. Back to the Nitrates.
To me it seems that such a drop in a short amount of time is just weird, and I can scarcely believe it. Nothing I have seen in the hobby seems to happen "over night" (except tank crashes.lol), especially when dealing with water parameters. Could it be the sand bed is catching up quicker than I expected?
Is it normal to see such a shift so quickly? I don't have any algae in the tank other than Chaeto in the sump that is lit for 12 hours a night.
Perhaps the combination of DSB starting to mature, with export from the Chaeto?
<If the sand bed was alive, there is a possibility this could happen but it would be unusual for this to occur in such a short time.>
I want to get another test kit to see if I get the same results, but I figured I would ask and see if this is a normal occurrence, or perhaps verify my kit might be bad. The test kit is only a few weeks old and is from July 2011according to the lot number, so I assume they shouldn't be expired.
Unfortunately, the LFS was out of the Salifert kits at the time, and API was my only option. Well Crew, what do you think? Please help me out here.
<Unless Salifert has modified their Nitrate Kit, I personally do not like this particular kit.
The test sample is much too small to read accurately.  You might want to look at the new Red Sea Pro series nitrate kit.  Informational video can be found here.
http://www.youtube.com/watch?v=Mf7jXkNBmX8.   Do keep us updated.>
<You're welcome.  James (Salty Dog)>

Time For A Remote Deep Sand Bed? -- 11/16/11
Dear Crew,
Currently I have a 125g reef tank (~145g total volume with sump) mostly mushrooms, and some mini(mini-maxi) carpet anemones. At any given time, I have between a 3"-5" sand bed (due to current and sifting critters, more on that later on stock list). I am having a hard time keeping my nitrates below 20ppm. Nitrites, ammonia, and phosphates are all 0 (verified with Salifert test kits). I recently did a 30% water change and removed all forms of mechanical filtration (filter socks and sponges), which had a marginal effect to say the least. I am beginning to think that my problem lies in the refugium area. I decided to try out Seachem's De-Nitrate, which now I am thinking might be causing some of my issue.
<<Mmm, yes'¦a bit too 'coarse' for my liking as a refugium substrate. Would be prone to entrapping detritus'¦I much prefer a 'sugar-fine' aragonite for this purpose. And depending on the grain-size of the bed in your display, this too may be an issue re the Nitrates'¦perhaps a bit of stirring/siphoning/cleaning is in order>>
I am thinking about putting together a remote deep sand bed,
<<hopefully of sugar-fine aragonite>>
hoping perhaps that it might help drop the nitrates down, since I am not sure that the 15g refugium area would be enough if I made a 6"-8" sand bed and kept my big ball of Chaeto in there.
<<Will help'¦though a bigger vessel for the remoted DSB is always preferable>>
I don't believe my tank would be considered overstocked, though I am not too sure, as there are only 10 fish in there (breeding pair of Yellow Damsels, breeding pair of Watchman Gobies, Scopas Tang, Kupang Damsel, Engineer Goby about 10" long,
<<A great fish'¦though these are social animals that will do better in a group (e.g. -- 3 or more)>>
Maroon Clown, Threadfin Cardinal, and a Banggai Cardinal). As far as inverts I have
6-8 Emerald crabs, a cucumber, a Long Spine Urchin, a Pencil Urchin, and 4 Fighting Conchs. Is this too much for my 125g?
Any input would be greatly appreciated.
<<Swap out the Seachem medium in the refugium for a finer grained substrate as a start and see if/how it helps>>
Thanks crew!!
<<Happy to share>>
<<Cheers'¦ EricR>>

Biopellets/Nitrate Control 11/17/10
Greetings from California !
<Hello Jim>
I'm interested in using bio pellets in my 450 reef tank I'm putting together. I would be running it in its own reactor and carbon in another reactor. Would you recommend a similar set up for a 80 gallon frag tank w/ 50 gallon sump to keep phosphates and nitrates low?
<I'm not familiar with the product, but I have heard good and bad about it, but more good than bad. If it were me, I'd use ozone rather than screw around with that.>
Also, aside from a protein skimmer, would you recommend using UV or other media for a quarantine tank?
<UV has few benefits as it can only kill what comes in contact with it.
Will do absolutely nothing for an infected fish. Use of a Polyfilter or Chemipure is beneficial in increasing
water quality in the QT.>
Many Thanks,
<You're welcome. James (Salty Dog)>

Nitrate reduction, Marine  7/13/08 Hello all, thanks in advance for your help, yet again. <Hi> I've been keeping aquariums for years, and have a 46 bow reef tank with a regal tang, flame angel, frogspawn, zoos, Kenya tree, some leathers, button polyps, anthozoa spp, among other things. The tank has an established cleaner crew consisting of hermits, cucumbers, sand sifting stars, etc. <Both the tang and angel need larger quarters to live out their potential lifespan. The sand sifting star will most likely starve within a year, and sanitize your sandbed of all microfauna beforehand.> My question is, how can I get my nitrates low? I realize this is covered in depth on your site, but I have tried everything, and cannot get my nitrates below 25ppm. My tap water has 3ppmish- very low, so I do not use DI. I do regular water changes, and do not overfeed. I have a powerful SeaClone skimmer, and am running several canister filters (Fluvals), as well as many powerheads positioned to eliminate dead spots. I also have 3 mangroves. <Mangroves are of limited use here, macroalgae in a refugium works much better. The SeaClone does not have a very good reputation, are you getting good production out of it. The canisters may be the ultimate source of the nitrates, how often do you clean them. If they are not cleaned at least weekly the biological material they collect will build up and decay, producing nitrates, hence why they are sometimes called nitrate factories.> My tank is filled with well established live rock, and I have a 4 inch sand bed of fine-medium particle size. I tried Seachem DeNitrate, but it adversely effected my corals. I have not tried using a plenum, what are your thoughts on this? <Will not help is my guess, the DSB is already processing as much nitrate as it can.> Help! Thanks, Whit <Chris>

Was: Sea Star Regeneration? -- now nitrates and DSB 03/12/08 Hi Marco, <Hello Ross.> Thanks for your quick and informative reply. <No problem.> The sand has been a slow process. <Good.> When I started the was only a half inch to an inch of sand. Uniformly there is now at least 3 inches but there are places that have 4 or more. <Okay, 4 inches is considered by many as the minimum for a working DSB, but that also depends on the current and grain size, DSBs can work with 3 inches. I'd try about five inches for your 100 gallon tank.> I'm still working on adding more. I do have bioballs, but I bet they should be cleaned. What do you think? <Personally I'd try to remove them with time to see if there is any impact on the nitrates (they are sometimes referred to as nitrate factories). Especially if the water runs through them before it reaches the skimmer, bacteria on these balls do break down proteins before the skimmer can remove them.> I do a 30 gal change once month and try to do a 5 gal change once every week to two weeks. <Should be more than sufficient for your 100 gallon tank. I suppose this water is free of nitrates?> On a good day the nitrates are 40ppm on a bad day its 160 ppm which seems outrageously high. <Indeed and possibly a cause of the death of the sea star. I think adding more rinsed sand and slowly removing the bioballs will improve the situation. Overfeeding could be another reason for high nitrates, you probably know better than me, if you are feeding too much. If slowly removing the bioballs and creating a DSB should not help, my next step would be a better skimmer.> Thanks again. Ross. <Anytime. Cheers, Marco.>

DSB or BB, Deep Sand Bed Utilization 3/5/08 Hi Guys! <Hello> What would happen to the hobby if you were not there! <Probably see a few more sharks shoehorned into a 20 gallon tank.> As again I come back to you. I have 36"W x 30"B x 30"H reef supported by a 36 x 12 x 12 sump with a filtration using sponge (NO BIO BALLS). I have approx 80Kg of LR. I always faced a problem of high No3. Hence 6 month ago I decided to go bare bottom on the same tank. Today I again face the same No3 problem. So a friend of mine suggested I go for a DSB like his (wherein he got 100Kg of sand from a beach for his DSB) and add another 20 Kg of LR which he has spare with him. I was thinking of doing the same. But this time I want to make sure that my no3 issue is resolved once and for all. <The nitrate issue is often caused by overfeeding and too infrequent water changes, while a DSB can help, its not a magical bullet.> It also crossed my mind that the LR i am using could be faulty too. So my questions are: 1) Should I go for DSB or a BB is better? <Its a matter of execution really, but I use a DSB.> 2) Should i go for a complete new set of LR? <If it is more than a couple years old I would think about switching out maybe 10%, but no need to replace it all.> 3) If a DSB is the sand from the beach (clean) suitable? <I would not, the risk of chemical or biological contamination is too high.> Thanks in advance Regards <Chris>

Coil Denitrator Question, refugiums, using WWM     2/16/08 Hi Crew. Been awhile since I have been here which means all fish in all six tanks are doing well. I do have a question on a new thing Im trying that I can't find out much about is a coil denitrator. <Ahh! I tried to make these commercially... twenty some years back...> I made one and it is what it is just a big tube with coils running down the inside with a bunch of media in the center. <An apt description... Ours were contained further (to keep all in the dark, discount photosynthates (e.g. algae) in a "clam shell" (a close-able container), and fed a stock solution of carbon... various alcohols and sugars were tried... Nowadays I'd like to run experiments with some dilute organic acids (e.g. Acetic...)> I have seen little on what to expect from the water coming out and cycling time. <Mmm, have to experiment... and what one will get is going to be a function further of what the incoming water make-up water is... but the pH should drop, there should be less measurable NO3...> I let run one full day wide open and then shut it off for a full week with water sitting in it. I turned it on and checked the water coming out and I had zero nitrates and zero nitrites but the ammonia was high. Is that normal or will it cycle to the point where I don't get any ammonia reading? <Should... the water needs to run through slowly... as in a drip...> I was very excited when I did my 1st test and seen zero nitrates though but I don't want to swap them out with ammonia though. I have been struggling with nitrates in my 125 gallon since I set it up over a year ago and know about the bi weekly water changes cleaning of the filter sponges and filter floss on a weekly basis but never do I get my nitrates under 80ppm. <Yikes... you've read on WWM re?> Well once but that was months ago. All fish are doing well so I don't fear them getting sick but would love some help in getting nitrates down. <... Read: http://wetwebmedia.com/nitratesmar.htm and the linked files above> Im going to have to take all six tanks down in a few weeks and move them to my detached garage account of my house has to be tented for termites. Not looking forward to that but when I do Im going o try a remote DSB in the 125 gallon. I have read so much good about them Im hoping that will help. <Should... you'll likely be a convert, soon> The tank is a 125 gallon and is 6 feet long. Im not sure what size tank to use for the remote DSB? <... is posted: http://wetwebmedia.com/marsetupindex2.htm> Will a 20 gallon high make a difference are do you think that is a waste of time and to small? <Bigger would be better...> Is there a certain way to gauge that? I also have a 220 gallon someone gave me and want to set up but if I cant find a way to combat these nitrates I don't want to set it up with the cost of the weekly water changes it will kill me. Well crew as always thanks for any and all help. Your site has saved many a hobbyist from going back to drinking for a hobby Im sure. <Funny... it's had quite the opposite effect on me. Heeeeeee! Bob Fenner>

SW questions, Cnid. comp. and NO3 reduction  -- 1/26/08 Hi Crew, My first question is about lighting. I have a 10 gallon which is almost 5 years old. It has 4 different candy canes with a total of about 40 heads. Also four hairy mushrooms (browns with blue lines) that are from one original. <Would be very big trouble if introduced all at once...> All my other mushrooms (reds, greens and blues) have shrunk and just disappeared. <To be expected> In fact there always seems to be one that does great and the others either just hang in or start shrinking. <Bingo> I have 65w PC's. The bulb I currently have is 10k and it will need to be replaced soon. Should I continue with this or can I go with a 50/50. <I would not change> I plan on staying with candy canes and mushrooms. <And not add any more/other Cnidarians> I have lots of coralline on the glass and very little on the rock although it has started to increase on the rock lately. My second question relates to nitrates. I am under the impression that it takes a DSB to have bacteria to process nitrates and if I do not have a DSB then water changes and/or a skimmer will help reduce it, water by dilution and a skimmer by eliminating the source pollutants. <Actually, not so... for biological conversion (denitrification) requires some/any sort of hypo- to an-aerobic setting/media, very low flow rate through, thereabouts... Doesn't have to be... a DSB> The first 3 years that I had my tank my nitrates were usually around .20. But for the last 2 years it is zero and I do not have a skimmer and I change 1 gallon every week. Does that mean I do have some nitrate eating bacteria or is my test kit on the blink. I use one of the cheap test kits (AP's master kit). Thanks <Likely there is no appreciable NO3... Bob Fenner>  

Nitrate reductor water chemistry -- 1/2/08 Hi Everyone, <James> A Happy New Year to You All, <Oh yes> I have a Bubble King skimmer and an Aquamedic 5000 baby skimmer working on my system of 3500 litres. . I added an Aquamedic nitrate reductor 5000 a few months ago. The water coming out of the Nitrate reductor is messing with the skimmers bubbles and stopping them producing any foam. <Mmm... perhaps a different arrangement of where these devices dump, mix their discharges> The bubbles at the top become very turbulent.. I now know for sure it is the no3 reductor as when I remove it from the system, the skimmers start to skim within hours. Put the reductor back on the system and the skimmers stop all together. I have done this 3 times with the same results. If I put the reductor outlet pipe straight into the main tank it takes a little longer to affect the skimmers. If I put the reductor outlet into the sump (where the skimmer supply pumps are) then it effects them within minutes. <What sort of water quality test devices do you own? Would you please check the discharge effluent from the denitrator? It may need to be turned down> Could it be the reductors oxygen less water and low mv? <Yes> Is there anything I could do to the reductor water before it enters the main system? <Aerate it mostly... or add an ozonizer (which I definitely WOULD have in a system of this size/type) picking up, discharging the denitrator-mixed water in a sump...> The reductor really works. The water coming out is zero nitrates. I am controlling it with an mv control. My nitrates are high but I doubt they will come down much with the skimmers not skimming. I do also have a large deep sand bed. Many Thanks, James. <Mmm... do you have this DSB outside the main system? What sorts/amounts of foods? Have you a purposeful refugium, macroalgae culture here as well? I would look to other means to augment your overall filtration... Bob Fenner>

Re: nitrate reductor water chemistry 1/2/08 Dear James, Thank you for your reply/advice. <Welcome> The water coming out of the reductor has zero nitrites and zero nitrates. Anything else I should test it for? <pH> When the mv gets to -250 it turns on a supply pump and pumps water through it for a few min.s until mvs are -200 or so. This process continues 24hrs. <I see...> That's a great idea. Will this work? - I set up a very small tank with tank outlet pipe into the sump. It can be at the end of the sump near return pumps and away from skimmers. I hook up my ozonizer along with another small skimmer and another mv control. I can also aerate the water in the small tank with powerheads. If you like this idea I will get going on it straight away. <I do think this is spiffy> In answer to Bob - Yes, my DSB is in a 50 gallon tank and is 17cm deep. It is connected to the main system. I don't think it is enough for the 3000/3500 litre system. <Not even> Sugar fine aragonite costs as much as gold over here so adding more DSBs is too costly. <Mmm, time for some importing on your own perhaps... next vacation, business travel> I struggle to find macro algae here in south Africa. I may be able to get Caulerpa though, is that ok? <Likely so> I feed Ocean nutrition flakes, pellets, frozen foods, prawns, calamari, seaweed. Everything really. I have 15 big fish (tangs. trigger, angel) and 15 little ones (damsels etc.) I think with the skimmers not working properly the nitrates keep going up anyway. catch 22. Thanks again, James. <Welcome! Bob Fenner>

Nitrates, SW, RDSBs  12/07/2007 <Hello Craig!> HI I have a 265g tank that is mixed reef - but mostly LPS. I have an additional 70g circulating thru a sump/fuge and wet/dry that was modified to be a skimmer compartment. No bioballs just rock rubble. I did leave one drawer for a filter pad which I change weekly religiously. I'm running a 3600 pump and splitting it as return/spray bar. I also have 4 Koralia 4's.<A wave timer would work great with these.> I have a nitrate problem reading about 25ppm (Salifert) phosphates 0 (Salifert). Last weekend I did a 100g water change - no results.<Not surprising.> Second I have some diatom as a result of some RO/di problems that have been fixed. With w/c I still have some diatom but it is decreased. <Clean RO/DI water will help. Make sure you test your Ro/DI water with a TDS meter (Digital) and that it reads 0ppm> Third I have algae almost like hair but very short strands all over my glass and I have to clean it about every 2-3 days or it is EVERYWHERE. I don't have a DSB in my main tank but do have about 20lbs live sand in my fuge = to about 5" I also have Chaeto/mangrove.<Some phoSarHC from Warner Marine would help greatly.> I feed every other day homemade food along with Nori everyday ( I have 5 tangs). I can't seem to get the nitrates down - I thought 100g's would have done it but it didn't I need help!!! I have about 15 fish the largest one is a Naso about 6" all others are much smaller Please help. <This sounds like you could use a Remote Deep Sand Bed (RDSB). You can plumb in a separate tank or a Rubbermaid Trash can(13gallon) with about 24" to 36" of sand and after about a month you will no longer have nitrates detectable. The bacteria in the RDSB will consume the nitrates as they are Obligatory Heterotrophic Bacteria and use the nitrate during respiration. Here is a link to the RDSB... http://www.wetwebmedia.com/deepsandbeds.htm http://www.wetwebmedia.com/livesand.htm http://www.uberfrags.net/forums/showthread.php?t=1443 These links should help. After setting up a RDSB you should flow thru it about 400-600gph. The flow should be over the surface and not thru the sand bed like an undergravel filter would be. Until then, keep up the water changes.-Rich...aka...Mr. Firemouth> Diver

Nitrate Levels And DSB -- 11/29/07 Hello fishy-gurus!! <<Hee-hee! Eric here... Not so much a 'guru' as just a long-time hobbyist willing to assist/share my observations and opinions>> I got a few questions regarding DSBs and nitrate levels. <<Okey-dokey>> I have a 430 Litre reef system, <<Mmm, okay...about 113-gallons for those readers on 'this side' of the pond>> 5cm of sand-bed (consisting of crushed marble and aragonite CaribSea sand sugar fine grade) and nitrate levels of over 40 - 80 permanently. <<Yikes! Much too high, as I am sure you are aware. Just off-hand I'm thinking either reducing the depth of your substrate by half, or preferably, increasing the depth about three-fold should effect a change/reduction in Nitrates >> I'm using the Berlin system with about 25kg of live rock. Other than that there are two Aqua One powerheads pumping 2500 and 2200 litre/hour and one Rio powerhead of 2000 l/h which is attached to my Aquasonic Venturi Skimmer. Because I have a chiller I had to connect an Aqua One Canister Filter (500L/H) to it, which contains Sponge and noodles. <<Ah! A clue maybe! If you are not cleaning this canister filter media 'at least' once a week then this is likely the source of your Nitrate issues due to the decomposition of the accumulated detritus>> My inhabitants are: 1 yellow tang 2 maroon clowns 1 damsel 2 lawnmower blennies 1 white ribbon eel <<Pseudechidna brummeri? Hmm, have you had this creature long? Though maybe not quite as 'touchy' as the Rhinomuraena species...is still thought to be a difficult animal to keep>> And 2 redline cleaner shrimps, heaps of corals and hermit crabs and one huge anemone. <<Mmm, not a good mix...I hope the Actinarian doesn't decide to go on walkabout...>> I do water changes every two weeks of about 100 - 140 litres. I just read all I could on DSB on your website but do have the following questions: 1. If I want to add another 10 cm of substrate would it be ok to go half and half with CaribSea Aragonite and the other half of natural Ocean Sand (I live in Australia/Queensland on the coast). <<It's not usually suggested to use 'beach' sand due to the possibility/probability for introducing harmful elements/pollutants. But, if you are certain the sand can be collected from a clean source there's no reason you can't do as you outline. You might want to also consider treating/curing the sand just as you would newly collected live rock>> Other than the fact that the sea sand won't do much for my pH levels and the potential danger of introducing pathogens, will it do the same job for NNR? <<It will... Just as buying some sand from your neighborhood hardware or home store would>> 2. I read somewhere on you site that you mentioned that the canister filter would have to be cleaned regularly because of the filter media in it. <<Yes>> Does the media inhibit NNR? <<It doesn't 'inhibit' the process...but not cleaning the filter can allow nitrogenous compounds to accumulate faster than the DSB can process them, thus 'overwhelming' the process of NNR>> If this is so, I could just run the canister filter without any media in it!? <<Indeed...but why waste an opportunity? I suggest you use this filter to hold a 'chemical' media such as carbon or Poly-Filter...to be exchanged on a bi-weekly basis>> 3. What is the ideal amount of rock to have in my tank to help NNR? <<Hmm...whatever amount is necessary to render a Nitrate reading of 'zero' for the size and stocking density of your system and the quality of the rock used, along with your particular husbandry skills and maintenance habits... I don't mean to be flippant, but only you can really determine what amount is going to work through testing and experimentation. My preference is to minimize the amount of rock in a system to allow room for growth of the corals and freedom of movement for the fishes, and utilize a large DSB for Nitrate reduction>> 4. How much would you siphon through the DSB to keep it working perfectly? <<Sorry...you will need to clarify this>> 5. How is it that I am battling with such high nitrate levels and yet all my corals are doing well/growing and the cleaner shrimps are perfectly well, too. <<Well...are you certain of the efficacy of your test kit? I suggest you try testing with new/different brand kits to validate your readings. Perhaps your Nitrate 'problem' is not as it seems>> I've got the beginning of the year. The anemone was a white colour with pink tips when I purchased her, <<Bleached>> she is now completely purple. <<Excellent>> Is she busy dying? <<It would not seem so>> I thought I works the other way around, they start of purple and turn white before they die? <<Indeed>> All my live rock is also covered in purple coralline algae?? <<Sounds good>> Ammonia and Nitrite levels are Zero, pH forever 7.8 - 8.0. <<I would adjust this up a bit>> I'm struggling to raise it above 8.0 even when adding liquid aragonite regularly!! <<Hmm...do let me know your calcium and alkalinity readings and we can pursue this further...and do say what this 'liquid aragonite' product is as I suspect it is not of much help re>> 6. Do hermit crabs and other crabs add to your bio-load as fish do or are they beneficial (clean up crew) and therefore the more the better? <<They do add to the bio-load, as does any living organism. They can be beneficial and, depending on your point of view, they can be a bane. I do not keep hermit crabs due to their 'very opportunistic' eating habits, and I consider the commonly used Astrea snail to be more trouble than its worth...but...the vast majority of hobbyists do employ these critters as a 'clean up crew'>> Lastly- 7. One of the guys at the LFS advertised the Eco-System with Miracle Mud as so good that he hasn't done any water changes for 6 months and all his levels are ideal. <<No such thing as a magic-bullet... Regardless of the methodologies used, I'm a firm believer in regular partial water changes>> Have you heard of that and does the Eco-System reduce nitrate levels. <<I've not used the Eco-System methodology myself but have heard much good about it. And the owner/perpetuator of this system is a good and much respected friend of Bob's>> If I install one, can I have it running in conjunction with my Berlin system and 15 cm DSB? <<Certainly... I think it is a very good idea to have this or any other type of refugium methodology employed with any marine system>> Also would it work to add Miracle Mud to my canister filter without light and algae growth? <<No... The mud would prove to fine/would likely only cloud your system>> And sorry this takes so long, if I don't want to drill holes and go the whole way, would it help to purchase a hang on Eco-System (not big enough for my system) and run it with the Berlin system? <<Would still be of some benefit, yes...but much better to employ a larger vessel under the display tank...in my opinion>> I appreciate all your suggestions and really would like to sort my tank out. thanks so much in advance. Best regards, Jana <<I'm happy to help, Jana. Eric Russell>>

Re: Nitrate Levels And DSB -- 11/30/07 Wow, thank you so much!! <<Quite welcome>> That was so quick, too. <<Does sometimes work out that way. Though even at its longest, most replies are made within 24-hours of receipt'¦that is, if Bob has his way about it [grin]>><Oh yes, sweep, sweep. RMF> You guys must be taking a lot of time off to help others sort out their tank problems. <<Mmm, nope'¦no 'time off' as such for answering queries. We just fit it in when/where/however we can>> To clarify some points: The liquid aragonite is the 'AragaMILK' by CaribSea, and sometimes I actually have the feeling it drops my pH! <<Hmm, indeed'¦ I suggest you stop wasting your money'¦try simple Sodium Bicarbonate to boost your pH if needed. And do read here (http://www.wetwebmedia.com/marphalk.htm) and among the links in blue>> I measured my KH which is at 125.3 ppm <<Well, that converts to about 7.0 dKH'¦a bit low (should be between 8 and 12 dKH) and can't really say what my Calcium readings are - never had a test kit for that... :( I will maybe read up on its importance a bit. <<Yes please, all are tied together (start here and continue through the associated links: http://www.wetwebmedia.com/martstkitfaq2.htm)'¦and very likely your low pH is due to an imbalance of Earth elements/bio-minerals in your system. If you stop all dosing, and do a couple or three 30% water changes a few days apart you should regain much of that 'balance''¦as well as diluting the high Nitrates'¦temporarily>> You answered my question regarding beach sand with- <<It will... Just as buying some sand from your neighborhood hardware or home store would>>. Can one by "any" sand from the hardware store or would it have to be a specific one? <<An 'Aragonite' sand would be best, if available, for its buffering qualities. But any type of fine 'play' or 'pool-filter' sand will also serve>> Are there no chances of chemicals being in there? <<Will be fine>> My question: 4. 'How much would you siphon through the DSB to keep it working perfectly?' - What I meant was would you at water changes when you pump the water out, siphon through the sand bed to get the worst out with one of these "vacuum cleaners", or does this actually disturb the NNR process that's happening in there? <<You will find those who would disagree, but I prefer not to 'disturb' my DSB with such maintenance practices. Rather, I let the biota in the sand bed do any stirring/turning. You can add some Cerith and/or Nassarius snails to increase this activity if you wish>> I think I have read different opinions on your site - so is there a golden middle between vacuuming and not disturbing? <<Not other than utilizing the bio-turbators as I just stated'¦in 'my' opinion>> Before I emailed yesterday I had done a test on my nitrates with another test kit and the result also read over 40! <<Not good'¦not good at all'¦>> Anyway, I will get to my canister filter straight away, as I clean it may be twice a year only...Ooops. <<Oh my'¦ This is one habit you definitely need to change'¦once a week please! (No wonder your Nitrate reading is so high!)>> By the way, my ribbon eel I have had for at least 18 months now. And before that I had seen him at the shop for at least 6 months. <<Excellent'¦ Perhaps this Pseudechidna species really is a bit more durable than the Rhinomuraena species of 'Ribbon' eel>> He is completely easy - although, I have to hand feed him squid. <<With a feeding-stick I hope'¦>> He is totally unable to catch any small fish by himself (sometimes I would bring tiny fish home from my visits to the rock pools'¦hopeless.) <<Odd'¦ And do rethink this practice of wild-caught live foods'¦much risk of introducing disease pathogens/parasites to your reef system>> When I bought the Lysmata shrimps last year he got booted out to the quarantine tank for a few months because I worried he would snack on them. So I tried some shrimps from the rock pools with him and they survived and he was allowed back in the tank. <<Again'¦odd that the eel shows no interest re these small live food items>> The only fish I have not been able to keep is the emperor angel - I tried three and all died suddenly without any signs the day before...Naturally I'm a bit discouraged to give it another go as they are with the most expensive fish here. <<Probably due to your water chemistry/pH and Nitrate issues. But really, your tank is too small for the long-term good health of this fish, anyway>> Thanks again for your time and wonderful advice. <<I hope it is of use>> Best wishes, Jana <<Regards, EricR>>

Hi Bob, it's Niki...again. NO3 in Wholesale Marine Life facilities  -11/27/2007 Howdy Bob! Well you did say I could write you when I had a question.<smile> I just didn't tell you I have aloooot of questions. Hope I'm not bugging you too bad. I have an issue with NO3 in my invert system here, <Not unusual... in a wholesale setting> and have found out that there are a copious amount of bio-balls that are in a very hard to reach place. They have not been cleaned in a very long time. I know there are differing opinions on whether or not these are a helpful means of filtration. <In a changeable, large/ish facility with vacillating bio-loads... something like them... or fluidized bed technology is really a necessity. Must have something that can/will rapidly ramp-up to convert nitrogenous wastes. Unfortunately such mechanisms overdrive nitrification... resulting in excess nitrate> I did read through your FAQs but did not find any situation that correlated with mine. I don't like them, personally, I have seen a great number of tanks in my maintenance calls that have been helped tremendously by their removal and subsequent replacement with live rock. <Yes... this has been my experience as well> I don't have any experience with such large systems like ours (8500) <Yes... gallons...> so maybe there is a reason I don't know about that keeps them here, but my suspicion is that they were just designed in the bio-ball hey-day. <This is indeed the case. I was there for all the fits, retrofits of Quality...> My question is this..should I a) Not worry about my around 35-40 ppm of NO3? <Mmm, if it were me/mine... I would try to address, reduce this... Have you spoken w/ ChrisB re your concern here?> b) Rip out all the bio-balls and replace with live rock? keep in mind the bio-ball chambers are highly inaccessible, being underneath the holding tanks. <Yes, I know... requiring the dismantling of all above them. A pain in the keester> I would be concerned with a drain becoming blocked with the live rock. c) Break down the tanks and just clean the bioballs? d) Remove the bioballs and don't add anything? or e) some really obvious solution that is staring me in the face that I haven't realized, which is why I contact the guru's A.K.A. You! <IF there were room, I'd opt for placing LR in some large container (even pressurized like a big Tahitian filter or two) outside the existing... BUT if you're going to take the invert. system apart... the addition/replacement of the plastic media for the LR in part or en toto will likely be a good route to go... and last for quite a few years...> Anyway, I have some pretty unhappy coral (but some very happy clams!). Help? Thanks...you're awesome and way cooler then a bristle worm - Niki <Don't know... have seen some very gorgeous errantiate polychaetes in my time... Cheers, Bob Fenner> to Bob Hi Bob, Thank you for your reply, and yes I spoke with Chris yesterday and he explained to me the need for bio-balls in a wholesale setting. Thanks again for your input. Niki Englerth :) <Ah, good. BobF>

Nitrates and a cold water tank -- 09/21/07 Hi, <Hello Ross.> A year and half ago, two students set up a 100 gallon, cold, <approx. temperature?> saltwater tank for my classroom as a project. Since those students have now graduated, I have inherited the tank. <Nice. I will set up a similar tank in the future, too, in order to keep some species I see regularly in large subtropical-temperate systems.> As a result, I'm not quite up to speed about all there is to do to maintain the tank. Currently, there is a Magnum 350 canister with Biomax, a protein skimmer, and, I believe they are called, bioballs (round, blue, spiky plastic balls). The tank had two scup and hake (along with a few crabs) for a year. The nitrites and ammonia have been zero since the original cycling. Toward the end of the last school year, the nitrates started creeping up. I removed all the fish over the summer (just leaving two crabs) thinking that the bacteria would have a chance to take back control of the nitrate problem. Unfortunately, that didn't really happen. I've now added a number of invertebrates to the tank because I want to use them in the classroom. The nitrates are really off the charts now. <A number would be good'¦> (nitrites and ammonia still 0 ppm). So I have a couple of questions: 1. If the ammonia breaks down to nitrite and nitrite breaks down to nitrate, what removes the nitrate? <Anaerobic bacteria, but those primarily live in deeper sediments as well as inside of porous rock material. Anaerobic bacteria turn nitrates into gaseous nitrogen that leaves the system.> 2. What do you think created this problem? < Nitrates are what accumulates when feeding the fish. Most proteins in the fish food are ultimately turned into nitrates. That's no problem, can be handled.> I can do a partial water change (which I have done) but it doesn't seem to get to the root of the problem. <Of course regular partial water changes should be done in any tank (at least 5% per week), but a water change of 30% can only decrease your nitrates by 30%. As a consequence large water changes are expensive for marine tanks due to the costs of the needed salt. What you probably want is natural nitrate reduction (also known as de-nitrification). Possible options for you are (order of my preference in this case): DSB (deep sand bed), live rock (see below for more detail), a refugium with cold water algae, a small sulphur filter. Those can be combined. You also should optimise the output of your skimmer and clean it regularly. Some recommended reading: http://www.wetwebmedia.com/nitratesmar.htm http://www.wetwebmedia.com/nutrientcontrol.htm.> 3. Finally, one of the posts I read on your site said to use more live rock etc. But live rock etc. seems to be associated with warm water tanks, how do I go about getting it for my cold water tank? <It's not only bacteria that make the rock live. More recent studies come to the conclusion you also need all the other filtering organisms, critters like feather dusters and such to transport water inside the rock. Current and diffusion alone are not sufficient. Therefore, you'd need rocks from approximately the same temperature as your tank to have critters that can survive in the tank. I think most tropic critters would not survive, but that depends on the actual temperature.> Do I need to add new Biomax? <Am not a fan of such nitrate removers except for emergencies maybe. Of course new Biomax would remove nitrogenous compounds like nitrates, but it has limited capacity and if your nitrates are through the roof it will likely only help a short time until you need to get a new one.> Can you simply buy the bacteria you need? <Anaerobic bacteria will develop 'by themselves' in an anaerobic environment. In contrast to nitrifying bacteria I think they are not sold in bottles.> What can I do to reduce the nitrate levels? <Hope the suggestion above help. I'd start with a deep sand bed (can be seeded with sand from the unpolluted sea) and some porous rocks (read about curing live rock) in addition to regular water changes.> Any help would be appreciated. Thanks. <Cheers, Marco.> Ross.

Re: Nitrates and a cold water tank. Nitrates and a cold water tank, follow up -- 09/21/07 Thanks so much for your quick reply. <You are most welcome.> Of course, after I sent the email I realized I should have told you the temperature of the tank and the number and amount of invertebrates. The tank does have a chiller. The temperature is around 66-68° F. <Okay, thank you for the information. Tropical live rock creatures would probably not like these temperatures, it would be best to get sand and rocks at the coast.> There are about 4 small sea stars, 5 brittle stars, eight hermit crabs, 3-4 sea urchins, one Asian shore crab, couple of snails. (there were some small sea cucumbers but I think they were eaten by the sea stars). By the way, I live in the Boston area. I wanted the tank to be a close approximation of our coast so I could easily gather inverts and keep them for classroom use. For DSB (deep sand bed), should I just collect some sand from a local beach? <Sand from an unpolluted beach is fine. While sand grains, which are coated with beneficial bacteria, and all sorts of tiny inverts are desirable, detritus is not. I would put a few pounds of sand in a bucket, fill the bucket with water, stir the sand, remove the dirty water and repeat until the water stays somewhat clear while stirring. In addition I would not add all the sand to your system at once, but prefer adding a few buckets at a time. Finally it would be good to aim for at least 4'/10 cm of substrate. See http://www.wetwebmedia.com/deepsandbeds.htm and the linked FAQs. Typically it will take some weeks until stable bacteria populations, that remove nitrate, have established in the anaerobic zones, but once the deep sand bed is active it can be very effective.> When doing a water change, I guess I shouldn't vacuum deep into the sand bed as that might expose what anaerobic bacteria I do have to oxygen. Or am I misinterpreting that? <You are absolutely right. Just vacuum detritus at the surface if necessary.> I do have a little bit of macro algae (Chondrus crispus). I've only been leaving the tank light on for about 2 hours a day though. A year ago, when the light was on longer, we had a problem with undesirable algae growing. Remove the light, and the problem went away. Will more light help my nitrate situation? <It could, if the Chondrus crispus is growing fast enough to compete with the nuisance algae for nutrition. I'm sure the invertebrates would enjoy more illumination, too. As soon as the nitrates are low again, chances are not too bad that nuisance algae grow is limited and a somewhat more natural lighting can be introduced.> Thanks so much for the recommended reading. They were very helpful. <Thank you for sharing your most interesting project. Marco.> -Ross Nitrates, canister, BioWheel -- 07/26/07 Hello, <Hi.> I'm writing to you today, because I have a problem with nitrates in my tank. I have a 46g Bowfront that is currently a FOWLR setup. For filtration I use a Coralife 125 SuperSkimmer, 15w Gamma Ray UV Sterilizer and a Magnum Canister filter. I know high nitrates are stressful for fish and I'm also in the process of converting my tank to a reef, so lowering nitrates is a priority. Ammonia and nitrites are 0, but nitrates are 50ppm. The only fish in the tank are a harlequin tusk and 3 damsels. I believe the canister filter is the cause of the nitrates and I want to know if it is possible to run my setup without it. <Yes, if your skimmer is working properly and you have about 45 pounds of live rock and enough current. I'd use the canister only for additional flow and mechanical filtration with easy to clean foam (needs to be cleaned often, at least weekly) and for carbon if needed. Carbon can be quite beneficial in a future reef setup.> It keeps the water clear, but the constant maintenance of replacing the carbon is a real hassle. I was considering adding a double BioWheel hang on filter in place of the canister. <Is possible. I'd prefer live rock, DSB, a small mechanical filter (if you really want to replace the canister) and, if possible, a sump or refugium, but it's your choice. See http://www.wetwebmedia.com/nutrientcontrol.htm and http://www.wetwebmedia.com/marine/setup/filtration/biological/biofiltr.htm for further opinions. And don't forget partial water changes to decrease the nitrates.> My concern is that this will cause a mini cycle while the bacteria establishes itself on the BioWheel. What is your take on this? <Can happen. Therefore, I'd add the BioWheel hang on (if you decide to use it) while the canister still is connected and can deal with unwanted nitrogen compounds from the BioWheel. Dirt from the canister can be used to seed the BioWheel.> Thanks for reading, I'm looking forward to some great advice. <Hope you like it. Cheers, Marco.>

Another DSB/Nitrate Reduction Question -- 06/23/07 I have a 58gal tank + sump with approx 45lbs live rock, crushed coral substrate. <<This last is likely a large contributor to your Nitrate issue>> A Finger Leather, a few Mushrooms, Xenia, Zoanthids and some Yellow Polyps. <<But for the Xenia, quite a noxious combination>> All are small and well spread out. <<But in a relatively 'small' volume of water'¦do employ some purposeful chemical filtration (Poly-Filter/Carbon)>> Livestock = Yellow Tang, <<Tank is not big enough for this fish, mate>> Maroon Clown, Royal Gramma and a Sixline Wrasse + Snails and Hermits. <<Not that you should consider it now, but if things change, that Pseudocheilinus will make future fish additions problematic>> Protein skimmer that makes about an 8-12oz of dark skimmate a week. My nitrates are consistently in the 20s. <<Ah yes, this needs to come down. It's hard to say for sure but, perhaps you need a better/more efficient skimmer>> 5-gal water change every 2 weeks with aged RO water. <<Allowing the salt mix to 'blend' for several days I hope>> It's understood that by increasing water changes, I will dilute the Nitrates, but I do not want to have to do this on a permanent basis. <<Mmm, understand the mindset'¦but on this small volume this is an inexpensive and most healthful process. And doubling the volume to 10-gallons could make a very big difference here>> Reduced feeding does not seem to help reduce the Nitrates. <<Coming from somewhere else>> It seems that I have a lot of debris in the crushed coral even after using a gravel vac. <<Course substrates can be very problematic>> I have taken some crushed coral out and cleaned it but I am afraid to do a lot at once for fear of shocking the tank. <<Mmm'¦may not be much of an issue if the existing depth/volume is small>> I think that a DSB is the way to go. <<I am a strong proponent of this methodology>> After the DSB is up to par I would add more live rock. <<Don't act too quickly re the rock'¦fishes need room to roam>> At the present, 100lbs of pet store aragonite is not in my budget. <<The retail side of the hobby IS proud of this stuff>> I see 4 ways to get to my goal of having a DSB. 1) Remove all of the crushed coral at once and add a bag at a time of aragonite over several months until it reaches the 4-6 in. depth. 2) Add a 12x16x4 DSB in the sump inside a plastic container and then do the above. 3) Wait until I can get enough sand to do the change at one time. 4) Wildcard option, to use limestone play sand that I found in a local Home Depot (Chicago region). It did pass the vinegar test, but it does not say where it is from. The pallet is in a slot marked Old Castle but I did not see Old Castle on the label, I can/will check again. <<This is probably not Limestone but rather Aragonite sand'¦and most desirable/useful as such re our hobby>> If these were your choices, what you would do? <<Hmm, a combination of all these choices! I would purchase sand from Home Depot'¦add the DSB to the sump and wait a week'¦remove the crushed coral from the display and add the full depth of sugar-fine Aragonite to create the DSB'¦ And do consider rinsing this sand before adding to the display. Some authors say this isn't necessary'¦and on new systems it is less of an issue'¦but I speak from experience when I say you will not like the result if you merely dump this sand in to your existing display without rinsing away at least 'some' of the 'fines'>> Until the nitrates are lower, I will not add anything and will have to increase the water changes. <<Good>> I consult the WWM regularly and am thankful to all of the crew for the comprehensive site. <<The 'Crew' is happy you find the site useful>> I do not understand how you all have the time and patience to answer our repetitive questions. <<Hee-hee! Can be trying at times for sure'¦but the greater good we 'know' we are doing far outweighs the occasional inconvenience or thoughtless/selfish querier. And to be fair, the 'Crew' has it easy compared to Bob who must 'handle' all the queries we leave, as well as maintain the site/post all for the public's edification>> After reading your daily questions for a while, I have come to the conclusion that many of us who ask questions (myself included) are not ready to accept the hard truth; we want a magical cure to Ich and other problems, as in my case Nitrate reduction. <<Ah yes! Tis true many write in looking for validation for something they know is wrong, and subsequently refuse to accept the 'hard truth' as you say'¦but by far the majority of folks are just looking for some 'personal' attention/guidance to their dilemmas. And as we often tout here'¦nobody should rely on a 'single' source for their information anyway. Hobbyists should research/attempt to gain information from a variety of sources (books, NET chat forums, WWM, hobby clubs, etc.) and use their own good judgment to choose a course of action'¦WWM is just one cog on the wheel>> Thank you! <<Quite welcome'¦and 'thank you' for this opportunity to rant [grin]. Eric Russell>>

DSB questions 6/6/07 Hi Crew, <Ed> Thanks for all your help so far. You've been an invaluable resource in helping this noob get started on the right foot. I have a 42 Hex with 40 lbs LR, a 3 inch sandbed (mixed fine live sand and CC), 175 MH pendant, Remora skimmer on MJ1200, and a rio400 powerhead for added circulation cycling for 5 weeks now. What's in there so far is the cleaning crew (2 skunk cleaners shrimp, 1 sm. brittle star, various hermits and snails) and a couple small frags (few Zoa buttons, GSP, 1 sm Xenia stalk, 1 sm mushroom) and no fish yet. I do a once a week 5 gallon water change and top off with RO/DI water. Everything is doing quite well. My question is about the sand bed. My nitrates have been sitting pretty steadily at 5-10ppm. I was concerned that maybe my sand bed is just a bit too shallow or coarse. Might this be the case? <Mmm, yes... and your system is new...> I've read that DSB's will perform differently depending on the situation and my tank is taller than it is wide, hence lower surface area. Can I add more fine live sand at this point without affecting the tanks cycle? <Likely so, yes> Would this even help? <Ditto> I did just add 10 Nassarius snails this week. Before that, nothing was really sifting through the sand which I realized after some research is quite necessary. Would more sand stirrers be beneficial? <Not really> I guess 5-10ppm nitrates isn't that bad and maybe I'm just being impatient, but I'd like to see them at 0 before adding any more livestock. Thanks so much for you time =D Ed Gambler <Mmm, will likely never be zero here... w/o the addition of more outside filtration of a few possible designs... I take it you have read on WWM re Nitrates and their control. Bob Fenner>

High nitrates -- Proper skimming and natural nitrate reduction should solve the problems -- 06/05/07 I live in South Florida and after hurricane Wilma last year I experienced 11 days with no electricity. For the first 3 days I had nothing and for the next 8, I had 8 hours a day of filtration thanks to my neighbours generator. Ever since that time I have been battling very high nitrates. <It might have been good to give specific numbers to work with.> I have a 100 gallon tank with 75lbs of what I think is still live rock, 4 medium fish, some soft corals and a 20 gallon sump with a bio rocker filter. I have to get a new power head for my protein skimmer and I have not put my plenum back into the system loop. The protein skimmer has not been out of the system for too long but, I never really get a lot of output. <Re-calibrate your skimmer or get another one if not possible to get better results. A good skimmer in a well stocked tank should produce at least 1 cup of waste per week.> I recently did a 60 gallon water change and changed the sand with no help on the nitrates. <It would have been good to know how high the nitrates were after the water change. I hope you used a water source free of nitrates e.g. R.O.> My problem is I want to make the necessary changes to the tank to get it healthy again but I do not know where to start. Should I change the media in the bio rocker, add to or completely replace my live rock, do continuous water changes? I don't know what to do first, so that I don't make more problems. <Improve protein skimming to decrease further nitrate production as much as possible. To decrease the already existing nitrates continue doing water changes. Macroalgae such as Chaetomorpha and/or a DSB in your sump or a refugium are a big help to keep them down, too. Personally I do not like or use wet/dry filters. See http://www.wetwebmedia.com/reeffilt.htm and http://www.wetwebmedia.com/nitratennr.htm .> Please HELP! I want my fish and the rest of my tank to be safe and happy. Thanks, Robin <Cheers, Marco.>

Nitrates reduction 6/4/07 Hello Bob and/or your fellow Crew members! <Hello> Again, thank you for the wealth of information you provide on WWM. I have learned so much from your site and can literally spend an hour a day reading and learning. Truly amazing the amount of information you provide and it is so appreciated. <Lots of stuff here for sure.> I have questions about Nitrate control. I have read your FAQ's on the subject and have learned a great deal of info, but am hoping you can give me some information specific to my tank. I am new to the hobby. I have a 55 gallon Hex (I know, not ideal, but it is the tank we had to work with). <As long as you are aware of your limitation.> No sump/refugium, and at the moment neither are an option. <There are decent hang-on-back models for refugiums if you are interested.> We have a Fluval 305 canister filter, a Bak Pak 2+R skimmer, and 3 power heads. Between the filter, skimmer, and power heads, we have approximately 750 gallons/hour of water being circulated. I know with a hex, the gas exchange isn't great, so I decided to have enough power heads to give me good water circulation. <Good> I have about 30 pounds of cured live rock and 20 pounds of base rock in the tank. I have a 2 inch substrate consisting of 30 lbs of sugar fine aragonite mixed with 20 lbs of Carib-Sea Arag-alive live sand. After reading on your web site, I realize this depth of sand bed may is either too deep (over 1 inch) or too shallow (under 3 inches) to aid in ridding the tank of nitrates. <Yep> That being said, I have a healthy population of copepods, amphipods, and bristle worms already established in the tank, and there is a good amount of some red macro algae growing from my LR. The tank has been cycling for 2 months with no fish. <Good> For the duration of the 2 months, the ammonia and nitrite levels have remained at 0. Within the last 2 weeks, the nitrate levels have risen slightly to 5 ppm. I did a 5% water change last week, the first water change the tank has had as it has been cycling. Also added our first fish last week, a Midas Blenny. He seems to be doing well, eating well, has already found his favorite "nook" in the live rock but often swims about. What a great little fish he is. <Agreed> Testing my water parameters yesterday, my ammonia and nitrites were still 0, but my nitrates had risen to 10 ppm. I am sure the addition of the fish, with the feeding and waste being produced is contributing to the higher nitrate level, but I am wondering what I can do to prevent if from rising even further. Based on what I have read on your site and in other literature, I know Midas Blennies like frequent feedings. I have been feeding him frozen Mysis and flake food in small quantities twice a day. <Replace the flake food with pellets, better for the fish and less release of nutrients directly into the water.> He seems to gobble up whatever I put in the tank, and acts as if he would like more food. <A sign of good health.> I am so concerned about overfeeding that I am being very conscious of the amount of food I am putting in the tank. <Good> That being said, I still wonder if I am feeding too much for this fish even though he "appears" to eat everything that goes in. <If it is gone quickly likely ok, 30 seconds to 1 minute to consume all the food.> So my question is, with my set-up, tank limitations (no sump/refugium an option at the moment) LR and sand bed depth, livestock/feeding habits, what would be your recommendations to keeping my nitrates under control? I plan on 5% water changes every week, and my skimmer has started pulling much darker gunk from the tank since the blenny was added. Should I reduce/increase the depth of my sand bed? <Could, would be a good idea.> Any feeding suggestions specific to the Midas Blenny so he remains well fed without being over/under fed? (I looked for this info on the WWM but didn't see any info specific to Midas Blennies). Or is this just a case of my tank still cycling and me needing to demonstrate more patience? Any insight you could give would be greatly appreciated. One last thing, I promise! :-) Every time I attempt to register to become a member of your site, I see a message that says registration is temporarily unavailable. I have received this message for the last month. I would love to register so I can post some of these questions on the message boards. Any idea when registration for new members will become available? <It actually a separately owned and operated site, but I'll send a note over to the mods there and see if they can take a look.> Thank you once again for the reply. I really don't know how I could have come this far in the hobby without your insight, advice and support. Jamie <Nitrates take some manual work to get rid of. You could slowly add to your sand bed, maybe 1/4 to 1/2 inch a week. Either way clean your Fluval very often, weekly for sure, and move up your water changes to 10% weekly (5 gallons). This should help lower them, although I don't consider you in the danger area yet.> <Chris>

Just when you think all is fine...WHAMMO!  Thirteen fish dead...  GFCI use, alcohol use (in denitrators mostly)   5/21/07 Hi Bob, Not to solicit sympathy, but because I know you would care/be interested to know... <Oh oh....> A faulty GFCI (still investigating but this is where the finger is pointing) tripped sometime <Do this... even go bad w/o any notice...> after my last look at my tank on Saturday night and was not discovered until mid-morning Sunday while the tank was still dark when I noticed the drop in water level in the display.  This circuit happened to be the one my sump return pump is on.  By the time I saw there was a  problem and got the system running, twelve fish were expired and the remainder were in severe distress from what I have concluded was oxygen deprivation. <... bunk>   Normally with good circulation (the Tunze pumps) I would expect my tank to be able to maintain acceptable oxygen levels, but about an hour before the tank went dark the night before I had dosed 6ml of Ethyl Alcohol and believe the resultant bacteria boost consumed the available oxygen faster than water circulation could handle without support from the sump/skimmer. <Arggggg! Am sure you've seen my rants re such feeder stocks to boost anaerobiosis...> Of the initial survivors, the Yellow Tang never fully recovered equilibrium and died several hours after discovery.  Amazingly the Copperband Butterfly was/is still alive and is swimming upright but seems disoriented/confused, as well as light sensitive, and will not eat...not a good prognosis.  The pair of Orange-Tailed Damsels seem unaffected, as does the Dragon Goby. The Yellow Wrasse (H. chrysus) is very active and appears to be swimming well but is not eating though it did show more "interest" in food than the Copperband.  But most surprising to me...the pair of Leopard Wrasse popped out of the sand bed shortly after the lights came on and are actively cruising, browsing, and ate well when fed! <Thank goodness> I can only guess the effects of oxygen deprivation would be much the same on the fish as it is on us/any animal, and only time will tell the full extent of damage.  Eric <Yes... sorry to realize your travails. Socios miseris habuisse dolorem dicet. Cicero. BobF>

Re: Cleaner Shrimp Killer...Those Tangs Are NOT "Reef Safe" Fishes After All! - 05/22/07 Oh NO...I'm sorry to hear you had some tragedy with your system, Eric. <<Thank you Linda>> I hope someone was available to help you in some way as you are always available for people like me. <<Nothing for anyone to do....  A faulty GFCI cut power to my recirculation pump overnight, resulting in the loss of thirteen fishes (375g reef display).  This alone would not have been problematic, but shortly before lights-out I had dosed Ethyl Alcohol to boost bacterial populations.  The resultant increase in aerobic activity quickly consumed the available oxygen once the recirculation pump was shut off and the skimmer was no longer providing oxygen-saturated water to the display...at least that is what I have surmised>> Wish I could help...Linda (in very dry GA) <<Your expression to do so is enough.  EricR...in similarly parched SC>>

R2: Cleaner Shrimp Killer...Those Tangs Are NOT "Reef Safe" Fishes After All! - 05/22/07 Eric, that is heartbreaking. <<Indeed...a saddening event>> I am truly sorry. <<Thank you>> When things that massive happen it tends to make me wonder whether we should have these precious items in our possession...but, then if you are like me, I LOVE the ocean and having a piece of it in my home is so gratifying and well appreciated, and never taken for granted.  So, what do ya do? <<Mmm, even 'small' losses are not to be taken lightly, but my best advice here...don't let such events cause 'knee-jerk' reactions...and above all else, learn from it - Cuiusvis hominis est errare, nullius nisi insipientis in errore perseverare.  Cicero >> By the way, the guy I bought that nice, great big cleaner shrimp from that my Hippo Tang had for lunch, had just told me the story about his Hippo Tang and what a holy terror he has been in his reef tank and said he was going to have to find it a new home! <<A more 'common' occurrence with these fishes/Tangs in general than many realize I think>> He said his Hippo Tang is ripping his fish apart. <<Yikes!>> Geez!  He said he really likes the fish, though, because when he had ordered live rock, the fish had wedged himself inside one of the crevices in only 2-inches of water and when he went to place the rock in one of his tanks, out came this little Hippo tang!  He couldn't believe how he survived. <<Amazing...and further testament to just how sturdy many marine fishes truly are>> I just discovered this guy's new fish store.  It is beautiful and he only deals in saltwater. <<Sounds like my kind of place>> He has fish, all types of corals and invertebrates.  A really nice guy.  The store is located in Flowery Branch, GA, in north GA.  Everything, the tanks, the water, looked so clean and healthy. <<Very nice>> I will go back to him, for sure.  (I want his job!) <<Hee-hee!  Tis LOTS of work!>> Keep on going, Eric...Linda in GA <<Never intended not to, Linda [grin].  Eric Russell>>

DSB question  -- 03/09/07 I am a huge fan of the DSB and have had great success with it in my 75 gallon reef tank at home (thanks to the info on wetwebmedia.com). I have now started a 65 gallon hex at work so I can enjoy my reef all day. I used a 6-7" Aragamax sandbed with 45-50 lbs of LR. I also threw in a couple scoops of sand from my DSB at home to seed it with some pods and worms. <Good move> I am running a micron filter pad in a small 5 gallon sump that is really only used for the pad, gas exchange, and some on and off skimming. I change the pad weekly and use RO for top off. I have 2 maxi-jet 1200's and the return pump is a Rio 2100, the tank seams to have pretty good flow and is quite turbulent top to bottom. It's stocked with a yellow tang, a small ocellaris and the usual assortment of janitors. Corals include a pom pom xenia, star polyps, assorted zoo's, 3 Ricordea yuma, and other various mushrooms and a few small SPS (basically everything is fragged from my main tank, free=good). My problem is, I can't get the nitrate down all the way to 0 (unlike my tank at home that has had undetectable levels for almost 2 years). It's currently around 15-20ppm, and after 4.5 months I can't figure it out. <Mmm...> I don't think the bioload is anywhere near too much and I feed relatively sparingly. Any ideas are appreciated on why this won't go into full on denitrifying mode and get me down to zero. <Is very likely the shape of the tank (hex) and relative small size of the refugium/sump... Can you add a small light and macro-algae there? Is there room? Maybe to expand it... Bob Fenner> Thanks so much, Jeremy
Re: DSB question  3/9/07 Thanks for the reply Bob. I do have some Caulerpa in the main tank, and was thinking about adding a light in the sump to move it out of the display area. <Good idea> Interesting theory on the shape of the tank, I hadn't considered that it would make much difference for such a lightly stocked tank. <Yes... less surface area and volume of substrate...> After seeing the power of DSB denitrification in my other tank I was dumbfounded when the same thing didn't happen in what I thought was a thicker and more robust DSB to begin with. I have noticed that an arrow crab I had in this hex obliterated the bristleworm population, he has since been banished to his own chamber in the refugium at home. Do you think this could be substantially contributing to things? <Mmm, possibly> I have thought about trying catch some bristles hiding in the rubble at home to reestablish them here at work. I attached a small picture, as you can see it's pretty thick. <Mmm, yes... but I also see that big Yellow Tang...> Thanks again for sharing your knowledge with us!! -Jeremy
<A pleasure. Bob Fenner>

NNR and Hang on Tank Refugium   3/4/07 Dear Sir or Madam: <Tim! "I am the knight who says, fish!"> Congratulations on running such a helpful website for us aquarium keepers! Thanks a million!  My boys and I have learned a lot from you guys. <Great!> We have a 75 gallon fish-only saltwater tank with 80 pounds of live rock and about 15 fish of assorted varieties.  We have been running this setup for about six months now.  We have been plagued by excess nitrate levels.  We now have a RO filter for water changes and try to observe best practices, but we still do not have nitrates under control.  I am getting sick of expensive water changes (sea salt ain't cheap). <Mmm, no... and tossing/switching it out is not always the best approach to maintaining good water quality...> I think a deep sand bed in our main tank would be very expensive.  However, I am considering adding a hang on tank refugium for the sole purpose of NNR. Is this practical?  Would it help?  How big should it be? <Will help... bigger the better... Would like to see you situate a bigger "outside" (with pump...) one instead... Please read here: http://www.wetwebmedia.com/refughangonmodelfaqs.htm and the linked files above... Bob Fenner> Thanks, Tim Swift Deep Mud Bed for NNR...Yes   2/25/07 Quick question.  Could a deep mud bed help with NNR as effectively as a DSB.   <Both deep sand beds and deep mud beds can successful reduce nitrates to zero more here:   http://www.wetwebmedia.com/nitratesmar.htm and here http://www.wetwebmedia.com/mudfiltrfaqs.htm also links in blue at top of pages.> If the answer is no, my follow up question is why not.  Thanks a million. <Welcome!  -Mich> Ari

Nitrate Reduction Question, Confusion with Remote Deep Sand Beds and Natural Nitrate Reduction.  2/7/07 <Hello! Mich here.> Just wanted to let you know that I use your site almost everyday to lookup answers to questions.   <Awesome!> On one of the posts for either DSB or Nitrate Reduction it was mentioned to take a 5 gallon bucket and place a Plenum in it and fill it with sand to create a nitrate filter.  A couple of questions I have regarding this; the way the mention made sound was to have the water inlet above the sand line and the water outlet above the sand line as well and let the water flow across the sand.   <Correct.> 1st question is how much rate of flow should go across this; the tank is 125 with a sump and a 30 gallon refugium also with a DSB.  I figured I would run an additional pump to get the correct flow.   <Minimal flow, a small powerhead should do it.> 2nd question is with the concern about the DSB becoming a nutrient sink, why wouldn't you let the water flow out the bottom of the plenum bring the water flow faster through the sand?  This would then prevent a build-up of the nutrients; wouldn't it? <No.  You are thinking on a macro level, for this you must think on a micro level.  Think biological filtration not mechanical filtration.  The point is keeping the deeper areas of the sand anaerobic or without oxygen.  This helps in nutrient breakdown, a means of NNR Natural Nitrate Reduction.>   Thanks <Welcome!  Hope that helps.  -Mich> http://www.wetwebmedia.com/nitratennr.htm http://www.wetwebmedia.com/dsbdepth.htm http://www.wetwebmedia.com/denitrification_erfaqs.htm Cary Meredith

Bio De-Nitrators  3/23/06 Hey! <Hi>     How's it going? The other day at the LFS I came across a Azoo Bio-DE-Nitrator. These are 2 cylindrical things (1feel long) next to each other. <Yep, am familiar> As per the box you are suppose to add some De-Nitrator liquid to it, which comes along with the box to the de-nitrator once in 3-4 days and you will see a good drop in the No3 and in long run will come across a stable pH. I was just wondering if these things work? Thanks for the help! Keep Rocking <Keep reading: http://www.wetwebmedia.com/denitrification_erfaqs.htm Bob Fenner> Nitrate Reducing Media...Which One Is The Best? Has any testing ever been done on the Nitrate reducing properties of the many over-the-counter filer media? Do any of the following products reduce nitrates? 1.  Matrix 2.  Cell Pore 3.  Bio-Glass 4.  Nitrex 5.  De-Nitrate 6.  Purigen 7.  Nitra-Zorb <I am not aware of any systematic scientific study done on these media and their ability to reduce nitrate. However, some of the products you mention are biological filtration media designed to provide an efficient and hospitable surface for bacteria to inhabit, and others (i.e. Purigen) are chemical filtration media which do have some absorptive capabilities. I think the bottom line is that no one media can do the job alone. Nitrate reduction is the end product of a number of things, particularly good overall husbandry. If your husbandry habits are good, then these products can be a valuable ally in your fight to reduce nitrate and improve water quality. Always look at the big picture! Regards, Scott F.>

Anorexic Anaerobic Bacteria  8/27/05 Dear Crew: <Paul> Six months ago, I started a 75-gallon reef aquarium with an inline 29-gallon refuge sump.  My plan for natural nitrate reduction (NNR) was to reduce nitrates to nitrogen gas by cultivating anaerobic bacteria with a deep sand bed (DSB) and live rock. <Okay> During the first 5 months of this aquarium, I performed 25% water changes every week to keep the nitrate levels under control.  I want to be able to reduce my need for water changes with NNR but this does not appear to be happening. Last month, I decided to wait 4 weeks before changing the water. While the ammonia and nitrite levels remained near zero, I found that my nitrate levels had climbed to between 25 and 50 ppm per the Salifert Nitrate Test. <High> I can add macroalgae to my refuge sump for nitrate export but I'd rather do that as a last resort. <Why?> Currently, my refugium is only used for water changes and houses an Iwaki MD30 pump, a Jager heater, an Ice Cap fan, and a Remora protein skimmer with carbon filtration. I need your advice on what I must do to achieve NNR with a DSB and LR in the main tank.  The DSB is 4" deep on average and contains sugar-fine oolitic Pure Caribbean Aragonite from Petroglyph.   While it is full of bubbles when viewed from the side and contains feather dusters, I see no bubbles on the surface of the DSB.  Most of the main tank's volume is occupied by live rock covered with purple coralline algae and Pachyclavularia violacea but no observable bubbles.  The tank has a generous 10x water flow and 300 watts of DE-halide illumination with fluorescent supplements. Everything else in the tank seems to be thriving: 1 Condylactis anemone (left end of tank) 1 Ritteri anemone (right end of tank) 2 Green Fiji Trees Discosoma mushrooms Rhodactis mushrooms Pachyclavularia violacea Palythoa Assorted button polyps Halimeda algae 1 Maroon Clown 1 Flame Hawkfish 10 Blue Devil Damsels 10 Pajama Cardinals Asteroidea sand-sifting starfish Turbo snails Hermit crab cleanup crew (1) What more must I do to cultivate the anaerobic bacteria needed to reduce nitrates to nitrogen gas? <Perhaps add a couple more inches of substrate... I would> (2) Are there nitrate-reducing anaerobic bacteria cultures that I can buy? <Mmm, unnecessary> (3) Has anyone succeeded in NNR with a DSB and LR in the main tank without macroalgae and frequent water changes? <Yes> My anaerobic bacteria are anorexic! <Heeee! Do consider removing some/all of the LR from the refugium, adding macroalgae and a reverse daylight photoperiod there. Bob Fenner> -Paul.

Re: Anorexic Anaerobic Bacteria 8/28/05 Bob, <Paul> I appreciate your reply and wish to pose some follow-up questions if I may. <Make it so! (Pulls down his tunic)> You appear to be suggesting that oolitic deep sand beds (DSB) are more effective in natural nitrate reduction (NNR) than live rocks (LR). <In general they are> (1) Is this confirmed by published research? <Mmm, yes... a cursory search of pet-fish literature... by Bob Goeman's, J. Charley Delbeek, Ron Shimek... maybe Stephen Spotte, Martin Moe will likely show> (2) How do LR's compare with DSB's in ammonia & nitrite reduction? <In established settings, about the same... Initially the rock is more "active", important... per weight, volume... but with time, the DSB> (3) Does the type of LR matter (Florida versus Fiji)? <Oh yes... in general, Pacific "rock" is much more "full of holes" than tropical West Atlantic types... much more useful in terms of "biological filtration"> Currently, the size of my DSB is restricted only by the large amount of LR in the aquarium.  I can remove live rocks to increase the size of my DSB.  Is this how NNR is accomplished without algal filtration? <One way> To answer your earlier question, I do not want to add macroalgae to my refugium because of my bad luck in ordering it.  My order of Gracilaria parvispora from Hawaii arrived with Aiptasia.  My order of Chaetomorpha from the East Coast arrived with Caulerpa.  Unfortunately, there are no local fish stores in my corner of Colorado. <Mmm, I'd look around... local fish club/s or the Net... and get some small bit of "pure" culture from a fellow hobbyist... Or have you tried Inland Aquatics, Terre Haute, IN? Morgan Lidster has a mighty fine reputation...>   My refugium cannot accommodate another DSB because I designed it to provide an upward current to suspend macroalgae.  I want to make NNR work with LR and DSB in the main tank and would appreciate your suggestions. <Can be done... though am a big/ger fan of DSB's being remoted, outside of main/display tanks> Thanks very much.  I very much appreciate your forum and I think that is greatly advancing marine husbandry. <Wowzah!> Best regards, Paul. <Bob Fenner> DSB (and nitrates) Question 8/18/05 Good Morning Crew! <Andrew> I've got a question, which might not have a simple answer (What does in this hobby? )..... <Don't know... and am afraid to expand on...> My question lies in the necessary size of a remote DSB in relation to the "primary" tank for Nitrate control.  I've read every (And there are a LOT) query regarding DSBs on this board, and the info in the Reef Inverts book by Anthony, and Bob, but I'm still not sure I've gotten what I'm looking for. I'm in the process of moving my tank, and will be setting up a 72G bowfront tank, with a 20G sump, and (roughly) a 4.5G HOB CPR Aquafuge for Pod production/Macroalgae. If I don't go nuts on stocking levels, would a 5-6" DSB in the Sump (Probably 2/3's DSB, partitioned for water inlet from tank, and the Eheim 1260 return pump) and Refuge be able to control my Nitrates at or very close to Zero? <Mmm, will definitely help... only practice can tell how much> If you need any further information regarding additional circulation, filtration, etc, let me know.  I just hesitate to add the DSB to the display tank as a 72G primary Aquarium isn't particularly huge, and I'm not very fond of the 5-6" sand bed look, <Me neither...> but if it's necessary, function will prevail over form. I realize a lot has to do with maintenance, stocking levels, etc. but is there an effective "rule-of-thumb" ratio of Nitrate-consuming sump/'fuge size to aquarium size? <Not as far as I'm aware, or concerned... the bigger the better... but no minimum, matching value... Just too many other factors to place in a string of variables in such an equation... foods, feeding, lighting... chemistry... temperature...> (I have this really bad feeling you're going to say there are too many variables to tell) <Heeeee! It may well be time for you to join our Crew, start answering queries...> I'd just prefer to add the DSB from scratch, instead of stressing the heck out of the livestock by adding it later should it not be adequate. <Will be fine... I say, go ahead!> Thanks for your help with the question,  and for the amazing amount of help and information you provide! -Andy <Glad to share. Bob Fenner>

Nitrates a palooza!  9/1/05 Hello how are you doing. I have a 75 gallon salt water aquarium with Volitans lion, porcupine puffer, tomato clown and blue spot puffer. <Too much...> I have a pro clear sump with UV light on return to tank, a red sea Berlin protein skimmer and 750 gph pump returning water from sump. I have had tank going for 5 years and nitrates always have been 20 ppm. I checked nitrates Monday 8-29 and nitrates were 10 ppm. I checked nitrates Wednesday and they are 160 ppm. <Yikes!> I don't know what happened. <Your tank, substrate "got old"> Everything is the same in tank nothing new. I did 40 percent water change Wednesday night. do you have any suggestions. The ammonia is 0 ppm, the ph is 8.2 and the nitrites are 0 ppm. Great web site . thanks Joe t <Need to change out part, add to your hard materials... gravel, rock in the tank... every year... Capitalize the beginning of sentences, companies, products, your name... Bob Fenner>

RDP vs. DSB for NNR  9/24/05 Is there any research or literature that supports the following conjecture? "In a refugium, a reverse daylight photoperiod (RDP) macroalgae culture will remove nitrates at a faster rate per square inch of surface area than an unlit deep sand bed (DSB)." <Mmm, not as far as I'm aware... both phenomena (macro-algae, DSB) are general quanta, qualifications... how much of what would one use, measure?> I want to research this because I am still deciding whether to build a RDP refugium with an upward current to suspend Chaetomorpha or an unlit refugium with baffles to support an oolitic DSB.  To reduce maintenance, I do not want the refugium to house both macroalgae and a DSB. <I see... well, I would use both... but for experimental sake, you could utilize one, then the other, try to draw some conclusion/s re their comparative utility. Bob Fenner>

Re: RDP vs. DSB for NNR  9/25/05 Bob, What's your "gut feel" for whether a DSB or a RDP macroalgae filter is more effective for natural nitrate reduction (NNR)?   <Mmm, the macroalgae> Suppose you have a refugium chamber with a 12" x 12" surface area and a 12" depth.  You have a choice of stocking it 6" deep with either oolitic sand or Chaetomorpha.  Twelve hours of lighting per day will be provided for the algae but the DSB will be kept dark. Assume the DSB is already stocked with anaerobic bacteria.  In your experience which option will remove more nitrates? Thanks, Paul. <The algae... for a few "extraneous" other beneficial, more steady reasons. Bob Fenner>

Siporax retailers ? Quick follow up Thanks for the response,  just a quick follow up.  No one locally (Cincinnati Ohio) sells Siporax and I can not even find a US company selling the product on the web.  Any idea where I might be able to purchase the product? Thanks again, Randy <I would try marinedepot.com and customaquatic.com Bob Fenner>

Old live rock and sand, nitrates Hey folks !! <Hi Victor> Been reading the info on your site a lot lately....if my boss only knew.  <Perhaps they do> I wish I knew about this site along time ago when I was first mesmerized by the reef tank I saw in my LFS about 4 years ago. I have a 55 gallon, with approximately 55 pounds of live rock and a 1.5 to 2 inch live sand bed. <You may want to make this deeper, shallower...> Only things in the tank right now are 1 feather duster, 3 Mexican Turbos and bout 18 or so Astreas (which have done an amazing job getting my algae problem, which of course goes hand in hand with a nitrate problem, under control. My yellow tang of which I've had since I originally set up the tank 3 years ago just died. Out of all the fish I had in there at one point or another its managed to stay alive to boss around the tankmates it had. Needless to say I'm very upset and was going to pack it in but I enjoy the hobby way too much so I've decided to stick with it and do my best to get it right this time. When I first started up the tank I ran a Magnum 350 with carbon in it and a Fluval 304 with the usual media. I have decided to go the DSB route aiming for 4 inches maybe 5 in the display tank and a sump with some live rock in it. <Ah, good> ATM I'm running the sump (which was a wet/dry till I yanked out the bio due to your wonderful site schooling me on what a nitrate factory it can be as well as any filter media) and have ditched the magnum and Fluval. I also run a SeaClone (I know I know) until I can get a hold of a remora which will be soon. It seems to be doing a pretty decent job with skimmate ranging from a light green at times, to a dark green almost black color other times. I plan on running the Magnum again either bare for the extra water volume or with carbon or nitrate sponge in it. I have also read about a product named Siporax that supposedly helps reduce Nitrates due to material its made from and its properties.  <Yes> Figured I'd give this a shot in the Magnum as well if I can get a hold of some but this will mainly be to help keep them it in check once it's under control. I'm running extremely high nitrates.. 200 or so according to the test kit I use at the moment. It's been about 2 weeks since I ditched the bio balls from the wet/dry and have done a 45% water change (while the tang was still alive) and recently a 15% change and I still get the same readings from the Nitrate test kit. I intend to take some water to my LFS that I've gotten to be a regular at and have them test it for me for piece of mind. I use bottled water when I do my water changes and I cant seem to lower the nitrates. I've tested the bottled water and it shows 0 Nitrates, but I'll have some of that tested as well by the LFS. Last test I did the results were: Ammonia - 0.25 Nitrites 1.0 and Nitrates the reddest red the kit had as a key(200). pH results come out @ 8.2. Am I correct in assuming that if I take the actions I've stated above it will help lower my nitrates along with say 5% to 10% twice a week water changes? <Yes, all will help reduce nitrates greatly> I have the same live rock and sand that I had when I set up the tank 3 years ago. Is it possible that the rock not so much the sand isn't doing its job anymore? <Yes... it should be added to, or a good part replaced... every year or so> I tend to see a lot of what looks like dust from the rocks on the sand around the rocks...I clean off the sand trying not to disturb the sand too much but a day later its on the sand again.  When I add the new sand to the tank is it ok to add it directly on top of the old sand and around the rocks or do I have to remove the rock then lay the sand. I'm asking cause if I don't remove the rock a good 2 to 3 inches of it will be under the sand. Does this matter at all as far as the rocks ability to do its thing?? <Can be added directly> I plan on keeping 4 maybe 5 fish... some hermits and some snails.  I thank you in advance for taking the time to read this email, I just needed to ask for myself cause reading so much info that I found on your site gets overwhelming and confusing at times. Victor <Take your time... consider all bit by bit... you'll do fine. Bob Fenner> 

High Nitrate Hi crew, I know that you have answered hundreds of questions on high nitrates. I am far from any authority on control of a marine aquarium and am more of a seat of the pants participant. Looking through your site and others it gets very confusing on the proper amount of aerobic and anaerobic bacteria and how to naturally produce these processes. <Almost no limit to the amount, space dedicated to denitrifiers> I guess the first thing to do is to try to explain the system that I'm using. Everything is pretty much custom made. The aquarium is 5,500 gallons, 45 feet long and 5 feet tall and 6 feet wide. <More like 10k gallons...>  I have (4) 3 hp circulating pumps, 2 at the tank (one is pumping the top of the tank, the other the bottom) and 2 at a remote pump room (50 feet away). I have 2 five foot tall protein skimmers and 4 ammonia towers that are eight feet tall filled with bio balls. <Much of the source of your nitrates here> Two filter systems (a sock type filter we filter at 25 microns for the bottom of the tank pumps, and a hurricane canister filter for the skimmer pumps). The fish in this tank are too numerous to mention, but all are pretty compatible (no sharks). The nitrate level is at 80 ppm we are doing 2 wc a week at 500 gal. a change. Last week I purchased 20 shaving brush to assist in removing nitrates and they just turned white. By the way we have 32 20,000 k fluorescent tubes across the tank that we change out every 6 months. I am not losing a lot of fish in this environment about one a month, but I would like to bring other specimens into the tank that does not tolerate such a high level. I would like to install a refugium into the pump room but if the plants will not survive in the tank I'm concerned on investing into something that will not work. I am also having the same results in my quarantine tank that I have in my office (300 gal.). Any help would be appreciated, thanks. Dennis <Dennis, do measure your alkalinity and biomineral (particularly free calcium) levels in these systems... Though you don't list biomineralizing life (except the macroalgae) the presence of these materials will aid you greatly in your reduction of nitrate content. I do suggest you rig up as large as possible a refugium... perhaps one utilizing Caulerpa such that you can illuminate it 24/7... otherwise, there are other mechanisms for lowering NO3 concentration... just none as simple and free of having to fool with. Bob Fenner>

- DSB and Nitrate Equilibrium - Crew! Please help me... On August 8th of this year, I "retrofitted" my 45G FOWLR aquarium with a 6" DSB composed of 1-2mm aragonite substrate, and some oolitic material as well.  Since then my nitrates have consistently remained in the 29-31ppm range (as measured with a colorimeter for accuracy.) Partial water changes do reduce the amount of nitrates present, however, after the water change, the nitrate concentration slowly rises again (about 4ppm a week) until it reaches that 29-31ppm mark.  I have heard of the concept of Nitrate equilibrium, do you think that this scenario is probable in my case? <Could be, but seems more likely to me is that your DSB just hasn't matured enough to provide any real benefit at this point. They are not plug and play, per se... they need to time develop the various levels of fauna that will at some point help consume the nitrate. Is akin to cycling your tank.> Given that the Deep Sand bed is only 4 weeks old, is it possible that it hasn't had enough time to establish enough anaerobic bacteria yet? <Exactly.> How many weeks should it take, and if this equilibrium continues, when should I look at other methods of nitrate reduction. <I'd give it a month or two.> I simply don't believe that 5 small fish (1 ocellaris clown, 1 Pseudo Fridmani, 1 Firefish goby, 1 sixline Wrasse, and 1 yellowtailed Blue damsel) could create that much nitrate. <Small amount of total water... makes sense to me.> They are fed very sparingly, I have a skimmer installed, (although not a good one, it's a Red-Sea Prizm.)  The 30 lbs of live rock are providing my biological filtration for me....  I don't understand the problem...  Is part of the problem that I'm not being patient enough? <Yes.> Richard    <Cheers, J -- >

Adding Live rock to F.O. system... >Good day Wet-Webbers, >>And good day to you, Lenny.  Marina here. >I have a 140 gal. F.O. system using Bio-balls/Protein Skimmer w/ 50/50 Actinic fluorescent lighting.  I have an aggressive tank w/ lion, purple tang, emperor angel, Foxface, harlequin tusk and Clown trigger.  Is it possible to add a large piece of Live Rock to my tank without changing lighting (or if so, enLIGHTEN me)  I thought doing this would help bring my nitrates down and secondly allow my herbivores to graze on the rock.   >>Of course you can.  Live rock generally requires no lighting unless it has photosynthetic animals or algae upon it that you wish to grow.  However, do know that if it is encrusted with such, it will quickly be consumed.  Also, please know that in order to reduce nitrates, you will need an amount of live rock equal to 1-2lbs./gallon of total tank volume.  A more efficient way to garner natural nitrate reduction would be to plumb in a refugium, where you can put in live rock, a deep sand bed (a.k.a. DSB), and grow macroalgae cultures that will help sop up excess nutrients, and they'll be removed via harvest of said algae.  Please search our site for all articles and FAQ's on refugiums (I do prefer this methodology to plenums) for complete setup and maintenance information.  Also, don't let anyone try to tell you that the wet-dry filtration method is a "nitrate factory".  You will end up with nitrates no matter WHAT method of nitrification is used, and their reasoning is logical fallacy, true sophistry.  What is needed is a method by which the nitrates can be further reduced to their components, ending with nitrogen gas.  This is well-executed utilizing the refugium with DSB. >Right now my tank has lava rock and skeleton coral with Puka shell (Aruba) substrate. >>Begin on our homepage http://www.wetwebmedia.com -->go to "marine aquarium articles" -->go to "set-up" -->go to the sections on natural nitrate reduction, plenums (you'll see what a PITA they are), deep sand beds, and refugia articles.  There's more information there than you can shake a stick at, and by the time you're finished you'll practically be an expert (ex-spurt?)!  Best of luck to you!  Marina

Accumulating Nitrates >I was wondering if you could help me out. >>I'm wondering, too.  Let's see, shall we?   >I have a 330 gallon reef tank with about a 60 gallon sump with bioballs. I am constantly fighting nitrates with only a very limited stocking of fish for this aquarium. I have about 400 pounds of live rock 300 from Kaelini and 100 from Fiji. The fish I have are as follows: 4" Sohal Tang 2" Flame Angel 4" Sleeper Goby 1.5" tank bred Percs x 2 2.5" yellow tail damsel I have two inch tubes in both overflows to the sump with prefilter and a prefilter in front of return pumps. Both return pumps are Mag 2400s. I can't seem to understand why I am having a problem with Nitrates in this size tank.  What is the best method for a reef aquarium for reducing nitrates? >>Well, normally I'd say water changes, SIGNIFICANT water changes would help.  I would also say (and am/will) that setting up a refugium would be your very best bet.  Combine the 'fuge with a deep sand bed (DSB) and after a while (these do take a while to "kick in") you will reap the benefits of natural nitrate reduction. >How could I convert my sump for such? I attached a drawing of my system for you to look at. I am confused on whether to use a DSB on one side of the sump and leave bioballs on the other or remove both and have a DSB on both sides. >>ALWAYS be careful and go slow when removing the bioballs.  You have an excellent amount of live rock, so I would first slowly remove the bioballs, combining with large (on the order of 50% or better) water changes.  Then, I would suggest setting up a separate refugium, though it may certainly be set up within your sump, but it makes for a bit of down time that the tank may not tolerate well.  Please look here for information on refugia and natural nitrate reduction: http://www.wetwebmedia.com/marine/setup/index.htm   http://www.wetwebmedia.com/deepsandbeds.htm >>Also, besides the large w/c's, to help get a quick handle on the high nitrates (which, by the way, you've never 'fessed up to!) you may want to install a good foam fractionator in the current sump setup.    >Have live rock as well, or even a refugium. Which way am I going to have the greatest success for removing nitrates? I have about 60 corals, LPS, SPS, Leathers, Clams, etc. Please help make my reef a better functioning habitat for my livestock, Thanks Ian >>My personal opinion is that you'll have best and most long-term luck setting up a separate refugium, and you may be able to eventually "wean" your system off the current sump setup.  Do follow the links within the links I've provided.  Marina

Going Deep (Sand Bed For Denitrification) I am looking for help with rising nitrates.  Current conditions: 90 gal tank, 20 gal sump, AIS-90 skimmer, Mag 9 pump, 2 - 401 power heads, wet/dry filter (used just as a sump) with all the bio balls removed, 50 micron filter pads on the drip plate, carbon and chem pure in the first baffle, 96 w power compact, ph 8.2, alk 300, nitrite 0, nitrate 40+, salt 22ppm, 78-79 degrees temp, 1 med hippo tang, 1 med yellow tang, 3 sm. green Chromis, 2 clowns, 1 med Betta, 1 med hawk fish, 1 green polyp, many plate and disc mushrooms, 1 sm xenia, 2" of LS, 75 lbs LR, lots of crabs and snails, did I miss anything important? <Water, maybe? Just kidding, LOL- sounds good! Make sure that you rinse and/or replace the micron pads often (like weekly, or twice weekly). Also- get the sand bed up to at least 3 inches. Two inched is too shallow to foster complete denitrification processes, but too deep to be fully aerobic...Not good for the long run...Go deep!> Nitrates were at about 60, 10 mo.s ago when you recommended removing bio balls and 25% water changes weekly, it worked.............. down to about 10. <Cool...>   Recently, over 3-4 mos.,  the nitrates have slowly risen from 10 to 40 - 60 range again.  I am doing 15 - 20 % water changes weekly, using Instant Ocean salt. <A good strategy, IMO>   Make up water is RO, bare bones, no phosphates.   I vigorously vacuum the LS when I change the water. Is that a problem, am I screwing up the LS by removing the good stuff? <Good insight...You might be disrupting the beneficial denitrification processes that are taking place in the sand bed. A deep sand bed (like 3" or more, minimum) can realistically reduce nitrate to undetectable levels in an otherwise well-managed system, if left undisturbed> Feeding is about a tablespoon of flake, every other day.  Skimmer output is erratic and I want to change the sump to keep the water level constant to the skimmer. <Excellent thought- it will make a noticeable improvement in the quantity and quality of skimmate (funny that I used the word "quality" to describe a bunch of crap, huh? LOL). Thanks.......Mike C. <Well, Mike- I think that you're on the right track. Kick up the sand bed height, keep up your otherwise good husbandry practices, tack up a "Do not disturb" sign over the sand bed, and I'm sure that you'll see nitrates head south in due time. Good luck, and hang in there! Regards, Scott F>

- DIY Denitrification & Anemone Feeding - Crew, <Howdy, JasonC here...> My nitrates are now super low,  between 0 to 5ppm in just 3 weeks on my 180 gallon Fish tank! The new DSB with live rock that I set up is working great!  Before the DSB,  I was getting nitrate readings of about 80-100ppm with my current fish load. I was doing approx. 15 gallons a week in water changes. Now I am doing only 7 gallons per week in water changes. About the setup... I siphon water down from the main tank into the DSB box , (approx 15 gph). using a very long 1/2" tubing, (approx. 30 ft. of tubing; 'coil method'). The out end of the tube is submerged directly in the DSB water column. By the time the water reaches the DSB there is very little to no oxygen in the water which allows the Anaerobic de-nitrification process to take place. I suppose the same process can be accomplished through the use of an expensive Coil Denitrificator Unit, (from what I read these units can tend to be troublesome, high maintenance , periodic feeding of bio media & cleaning required, very slow water drip rate). <You are correct.> I just wanted to let you know that I have had great success with my DSB de-nitrification installation and would recommend it highly to others. The total cost was not bad ... just around $93 and it's very natural. All the fish are all very healthy and I feed twice a day. <Time will tell... need to have the thing running for at least a year to call it an unqualified success.> $35 - 10 lbs fine live sand mixture with 5 lbs. Aragonite med. course crushed coral. $7 - Plastic 12"L x 16"W x 8"H  box that fits nicely in my expansion sump. Cut holes in each side for water out at the 3 inch water mark above the 6 Inch sand bed. $4 - 25 ft 1/2" tubing $20 - 5 lbs of totally cured live rock (small pieces) $10 - 1 dozen Large Mangrove Plants (1-2 '  tall) $12 - 24 Hour Lamp $5 - Batch of Caulerpa (Taxifolia) Total - $93 On another note, I have a question about a large Bubbletip Anemone I just purchased to host my 5" Gold Stripe Maroon clown.  I have read that it is only necessary to feed the Bubbletip anemone once a week? Shouldn't I try to hand feed it 3 times a week or is that too much? What is the best foods for this anemone and should I use Phytoplankton ... and if so, how many times a week. <Actually, a meaty food, diced up to small particles would be much better. Do check out this page on our site: http://www.wetwebmedia.com/anempt2.htm > The fish store guy did not seem to know that much about the Bubbletip and feedings. Also, I have 2 large Actinic Blue bulbs and 2 large 10,000 k standard fluorescent bulbs on the side of the tank with the anemone. Is this enough lighting for this anemone? <No.> Do I need to purchase the more intense lighting and spend big bucks? <If you intend to keep it for the long haul, yes.> I could not get good answers from anyone about anemones. <I would suggest reading through the multiple pages of FAQs on the WetWebMedia site as many of these questions have been asked and answered before and are documented there for your perusal.> Thanks! Chris <Cheers, J -- >

Re: Nitrate problem David, Thanks much for the quick reply!  This is a first for me hearing about the penguin nitrate factory!  (Again, a product highly recommended by my LFS <Hey they must be good sales people...you almost bought it!> -the same one that recommended I cycle my tank with a copper banded butterfly <HAHAHAHAHAHAHHAHHAHHAHAHHAHHAAHAH!!!!! It's sad how many people will actually buy the copperband and then return to buy another one when it dies. That is sad :( > :o)  (I didn't do that) Could you 1. Explain why the Penguin is this way, <Not just the Penguin but all forms of canister and wet/dry filtration. It's due to the efficiency of this type of nutrient processing. These types of filters can handle a lot of nutrients and the nutrient processing is very fast.  Nearly all filtration produces nitrates in one way or another but the amount of nutrients that can be processed through a wet/dry (for example) is way more than could occur using "natural" filtration. Therefore it produces excessive amounts of nitrate that cannot be used up in the aquarium. If an aquarium is lightly stocked this isn't nearly as much of a problem> and 2. Suggest an alternative? (I will remove the excess coral tonight by the way) <Okay...Have you studied any about DSB's or natural nitrate reduction? They are all the rage these days. Also a plenum system (cheap and easy to build but be sure to set it up correctly). You can find information about this at saltcorner.com Then add a good protein skimmer and live rock and you will have all the filtration you'll need! Or you could just use lots of live rock and a good protein skimmer with no special sand beds. It'll work. Doesn't need to be complicated...just efficient. David Dowless>

Knocking Down Nitrate! Hi everyone :) <Hey there! Scott F at your service!> I hate to be a pest but I couldn't find the answer to my problem on the web site and I am losing my mind trying to solve this problem. <That's why we're here!> I can not get my nitrates below 20 ppm in my 100 gal tank.  I have 100+ lbs of live rock and a 2" live sand bed, I do 5-10 gal water change weekly and have the following equipment on the tank: a Rena Filstar canister filter, a fluidized bed filter and a Remora Pro skimmer.  I have 3 scissortails, a purple and a red Firefish, a true percula clown and bubble tip anemone, a pair of scooter blennies, a mandarin goby, a colt coral, an open brain coral, mushrooms (many mushrooms), polyps, a devil's hand, a hard coral, an urchin, turbo snails, shrimp, crabs - both hermit and emerald, a sand star  and a Christmas tree feather duster. <Bioload doesn't seem too bad at all.> Does live rock and live sand lose its' ability to biofilter after time? p.s.- Bob- I love your book, "The Conscientious Marine Aquarist" Andrea Brown < I love that book myself...It's the I Chi of the hobby- the sum of all knowledge...the- well- you get it- It's my favorite, too!!!!... Well, if the sand bed is constantly being stirred up and the beneficial infauna (creatures that reside in the sand bed) are being decimated, the processes occurring in the sand bed could certainly be disrupted, if not completely shut down. Also, one problem I see right off the bat is your sand bed depth. The rule of thumb for sand beds in closed systems is 1/2" or less, or 3" or more. 2 inches is sort of a biological "no man's land", too shallow to be capable of reducing nitrate, and too deep to be aerobic...This is a recipe for nitrate accumulation and potential problems down the line. I'll bet that if you kick up the sand bed depth to 4 inches, and follow other diligent husbandry techniques, you'll see a rapid reduction in the nitrate level!> About 30 lbs of rock is new but the rest is a couple of years old. So is the sand.  How can I get the nitrates down?  I use B-ionic in the tank and feed frozen brine and Mysis - as much as they can eat in 3-5 min.  I feed filter feeder food to the rest.  Please give me some advice as to what I need to do to reduce nitrate levels. <A few tips here: First, examine your maintenance practices. Try performing small (5% of tank volume), frequent (twice weekly) water changes, using quality source water (RO/DI). This helps to dilute many organic compounds before they have the chance to accumulate and affect water quality. Utilize aggressive protein skimming, and keep tweaking your skimmer until you're getting at least a couple of cups a week of dark, yucky skimmate...and clean the skimmer often- a clean skimmer works better! The Remora is a great skimmer, so really work it! Also, try utilizing chemical filtration media, such as a high-quality activated carbon and Poly Filter media (I love them), and replace them often. Reduce or discontinue the use of liquid invert foods...If not properly administered, they can add enormous amounts of nitrate and phosphate to the water...Consider growing and harvesting some "purposeful" macroalgae, such as Chaetomorpha, Gracilaria, etc. in a lighted section of your sump. They will help utilize some of the nitrate for their growth...In the end, nitrate reduction is all about nutrient export. Try a few of these tips, and I'll bet that you'll see that nitrate start to decrease. Good luck! Regards, Scott F>  

Lowering Nitrate... Your site is great, I hope you can help me. <I hope so, too!> I have a lot of questions. <Don't we all!> I have a similar prob. that someone wrote to you about. I have a green moray with a gray spotting on its belly. You said it could be a fungus and to try a Furan based med. What would be some Furan based meds.? <"Furan-2" by Aquarium Pharmaceuticals is a good one. So is "Furanace" by Aquarium Products. There are others, such as Maracyn, by Mardel Labs... <<Mmm, not this antibiotic, Erythromycin. RMF>> Do check out these medications> Eel is about 2.5ft. long. I was feeding him squid (from my local grocery store) only for a while, then octopus from my grocery store. I was thinking that maybe the squid and octopus from the grocery store may not be fortified with any vitamins my eel might need. I have decided to go back to squid and silver sides from the pet store. <Well, you could "fortify" these items with a vitamin preparation, such as VitaChem or Selcon (my two personal faves). These can do the trick> During the last couple of days he has been thrashing about in the tank a couple of times a day (that I witness), like he is throwing a fit, extremely violent. I do not have any other inhabitants in this tank. Is this normal behavior? <Really hard to say...I'd be concerned that there may be some kind of potential environmental problem, such as measurable ammonia, plummeting pH, loss of alkalinity reserve, etc., or a possible parasitic illness that is bothering the fish, causing it much discomfort...Do look for a cause> Tank is 75g (upgrading next year to much larger tank) water temp 76F salinity 1.024 ph 8.4 nitrite  0ppm ammonia 0 - .50ppm <Should be undetectable! Do recheck to confirm this! That could be the problem!> NitrAtes are very high 200+ can't control, tried weekly (5g) weekly changes, monthly water changes, Nitrasorb. No success yet. <Lots of ways to overcome nitrate accumulation in closed systems. You could employ a deep sand bed (like 5-6 inches) to help foster natural denitrification processes. Also, consider a more aggressive water change schedule (like 2 weekly changes of 5% of the tank volume). Work your protein skimmer hard! Make sure that it's pulling out at least a couple of cups of dark, yucky skimmate per week...Feed carefully, and only as much as the fish will clean up in a few minutes...Don't let any uneaten food accumulate in the tank>     My next idea is to try a coil denitrator, do you know where I can buy one? <Not sure who makes one...But you could make your own with a few hundred feed of small diameter plastic tubing in a bucket, and feed system water into the "denitrator" at a proper rate...monitor the "product water". Anthony describes an easy-to-make version in his "book of Coral Propagation". Do try the above methods first...then go for the homemade denitrator...They really work, and are not too difficult to utilize...> I don't know if alkalinity would be a cause of the gray spotting. I don't have a alkalinity test kit yet. If the alkalinity is off too high or too low, how do you adjust it? <Buffer, my friend....Do read about alkalinity on the Wetwebmedia.com site...And do get an alkalinity kit- it should be a basic part of your "inventory". > Thank you, Ronnie New Jersey <Keep on having fun, and do investigate these ideas! Regards, Scott F>

Re: Nitrates >Hi Scott >>Marina here to help you today.  Scott V. is no longer with us, so I'm going to sort through all this best I can.  Hopefully, I won't be readdressing points already hit, or confusing things for you. >Thanks for your help with this and for your quick response.  Just to clarify those points that I was vague on.   1) The tank is 2 foot long x 1 foot deep x 1.5 foot height - So the fish are easy to find :) >>Ok, the way I know how to sort volume in rectilinear vessels is this way: multiply the three dimensions, then divide by 231 (the number of cubic inches in a U.S. gallon).  So, 24" x 12" x 18" = 5184/231 = 22.44 gals U.S. 2) The three fish are about 3 inches altogether 3) The filter is an Eheim 2211 4) The medium in the filter is called matrix. 5) The water we buy from an aquarium and is high quality - so it is definitely not a source of nitrates/phosphates. 6) The substrate is a sand. Not sure exactly but I think it is a reef sand. It was recommended highly by several people I spoke to. Its about 4 inches high. 7) Nitrates are at least 40mg/l 8) There is about 10kg of live rock which is cured 9) Since I have bought a skimmer, I have lost a lot of current in the water as I am using the air pump for the skimmer. There is a weak agitation of the water surface from the filter. Not sure if this could be a problem?! >>Surface agitation is key to allowing/enhancing the O2/CO2 exchange, as it is only at the interface of air and water at the surface where this occurs. >I have only recently and once removed a small amount of substrate - so this wouldn't be the source. 10) We are feeding the fish "marine green". As opposed to brine shrimp (when we started). Again, thanks for your help with this!  Hansel my starfish will be forever in debt ;)  Regards Simon >>Ok Simon, let's get this sorted.  First, your tank is still relatively new, and as such you *should* still be getting nitrate readings.  Skimming ALWAYS helps, but you've got to be sure you have it adjusted properly so as to get the NASTIEST, smelliest, most foul skimmate possible.  Please do have the source water tested, as phosphates don't just appear, they have to come from someplace.  If you are using (in addition to the "Matrix"--it's those ceramic noodles, yes?) activated carbon, this very well *could* be your source of nitrates.  Try removing it for two weeks, performing your regular water changes, and test again.  Phosguard will indeed remove the phosphates, but it's an additional expense that, assuming your source water is indeed pristine and NSW (near salt water) you shouldn't have to always use it. >>Now, as for the DSB, the biggest concern is that the sand grains are suitably sized.  Sugar (granulated here in the U.S., IIRC it's called castor in the U.K. and elsewhere) fine is what we're looking for.  It's preferable to use a calcareous sand, as it will perform two functions for you: buffer the water's pH above 8.0 and hold it steady, and it will over time release calcium into the water where it can be utilized by those organisms that require it (coralline algae, for instance).  However, this is not to say that you cannot use a silicate-based product.  You'll just not reap the other rewards.  One way that I've used to determine if something is indeed calcareous is to take a bit and put some vinegar on it.  It should froth or bubble, at least a bit.  Do you have live rock in the tank?  If not, it's always recommended, as it helps greatly, including with providing seed stock for your DSB. >>Now, I'm curious if you have a sump or refugium in use as well.  If not, please consider utilizing this technology (I really love the refugium, because you can situate macro algae that will sop up nitrates and phosphates, then you simply remove it and voila, eh?) in lieu of the canister filter.  Better oxygen saturation is one reason, as well as making it easier to add a more efficient protein skimmer in future.  In the meantime, add no more animals until everything comes to zero readings.   >>So, in summary, expect to have the nitrates for a while more.  The DSB will take the longest to culture, disturb it as LITTLE as possible, as these bacteria are a picky lot.  Watch the animals for stress, if you fear, then always do water changes.  Good luck!  Marina

Refugium sizes and nitrate reduction Greetings, I have a 300 gallon SW tank which has evolved over the past 8 years to the point where I would like to add a refugium, but have little room to do so. I bought the tank used, which was set up by the prior owner as a fresh water tank with overflow boxes to a wet-dry filter inside the cabinet.  I set it up after purchase as a SW, FO tank.  In doing so I removed the overflow boxes and drilled holes in the tank bottom and plumbed it with PVC pipe.  I thus have water coming to the sump at each end of the tank via the PVC pipe, and returned by a large pump in the sump to the tank.  I also have a large protein skimmer outside and next to the sump. Over the years the inhabitants of my 300 gallon have evolved from a community of very large fish to the following: a 12' horn shark, 7' sohal tang, a 7' niger trigger, a 4' flagfin angel, a 3' rusty angel,  a 3' coral beauty, a lineatus wrasse, and a few damsels.  I have two pieces full of mushroom rock that are doing quite well, and about 200 pounds of LR.  I would like to add some soft corals now but am concerned about my nitrate levels.  I change about 70 gallons a month, and my nitrates hold pretty steady at 40-50 ppm.  I would like to reduce that level before adding soft coral pieces.  From all the researching I have done, it appears that the best way to do this is with a refugium. Herein lies my problem. I have no room behind, above, or on the sides of my 300 gallon tank to add a refugium tank.  This leaves under cabinet space.  As things now stand, I have room only for a 10 gallon tank beside the sump (unless I put a 10 gallon refugium tank next to both the left and right sides of my sump --- the sump has 3 compartments: the center and right compartments is where the tank water drains into the sump, and the left compartment is where the protein skimmer returns water and the water gets pumped back into the 300 gallon tank).  If I replumb, which would be a pain considering the existing cut-to-size PVC pipe, I could fit a 20 gallon tank in the cabinet. Question: I know 'bigger is better', but will a 10 or 20 gallon refugium make an appreciable difference in my nitrate levels to be worth the effort here?  Is there a better option available to me?  Thanks for your help. Elliot Segel <You need more biocapacity than 20 gallons to off-set 300 gallons. I wouldn't think it is worth it.  You make no mention of substrate, but if it's crushed coral, it and the wet-dry are the culprits, along with possible overfeeding/leftover food. I would look into more LR, a deep sand bed (like 5-6" fine aragonite) slowly weaning off the wet-dry and using the mechanical filtration in the W/D, perhaps with carbon but no bio-balls or wet/dry to produce nitrates. Clean all sponges, filter media at least bi-weekly to prevent nitrate production, rely more on rock and sand which will reduce nitrates. Also think of base rock in sump for de-nitrification, place to put more rock/sand. Hope this helps!  Craig>

Excess nitrate Dear Bob: Before I begin I would like to say a I am an avid visitor to your website. I am forever researching all kinds of topics...also I have read your book many times and have used it as a reference on many occasions. Additionally, looking forward to seeing you at the Brooklyn Aquarium Society.  <Thank You Gene, I know Bob really appreciates your support and input!> Now for my question: My question is regarding a 110 gal fish only tank. About a year ago my nitrates were about 20ppm (fastest kit). Over the last two months my nitrates are now at 40ppm and I have an idea i would like to do to reduce them but I am not sure if it will really work. Right now i have approx 1/2" of crushed coral and shell substrate...just enough to cover the bottom of the tank. I was thinking of removing that and add approx 1 1/2" of live sand. Paul Hunt of "Practical fishkeeping" is setting up a fish only tank and is using 1 1/2 " of sand to help with reducing nitrates (this is where I got the idea from). Some additional stats before I move on: 110 gal tank 48"x18"x30" Lifeguard fluidized bed filter 2 Aquaclear 500's (contains Cellpore & Chemipure) CPR Bak Pak Skimmer 15w Aquanetics UV 3 regular fluorescent bulbs 120w total approx 11 hrs per day 12 gal water change each week Ph 8.0, ammonia 0, nitrite 0, nitrate 40ppm (i don't check any thing else), sal 1.019 temp 80 Livestock: Volitans lionfish Yellow tang Passer angelfish Cuban hogfish Crosshatch triggerfish Vlamingi tang Snowflake moray Regal (hippo) tang Cleaner wrasse one large hermit crab The above fish have been in the tank ranging between 7mos and 3 yrs. (I know your are going to say i am over stocked and you're probably right)  <Most assuredly so.> I think the Vlamingi tang, which I have had for almost 2 yrs, will be donated to a public aquarium here on Long Island where they currently have a reef tank that contains about 4 Vlamingi's already. I have thought about a plenum set up, which I have in my reef tank for the last three yrs and is doing well, but I think my stocking is too much for a plenum set up.  According to Bob Goemans he does not recommend a deep sand bed directly on the tank bottom, another reason I was thinking about only going with a sand bed of 1 1/2". I trust his judgment and research in that regard (he has also complimented you in his writings) Also, adding live rock would also be a possibility but a lot more expensive than just adding the sand. Back to my original question, I can easily siphon out the substrate I have and add the sand Nature's Ocean was what I was going to use) but will it really help? <Absolutely. The 1.5" of sugar fine sand (Natures Ocean) is in essence a de-nitrifying deep sand bed, just one of degree. Note: Nature's Ocean recommends 1 lb per gallon to accomplish this. There is no reason I can see other than overall tank depth and personal taste that a deeper sand bed wouldn't be your choice although a good degree of denitrification will be available with 1.5" of fine sand, perhaps more with your fish load. The live rock would definitely help with this process, seed the sand with additional bacteria, and provide some natural grazing for some of your fish. PLEASE make sure any rock is well cured and smells like good clean, healthy, ocean. The nitrate is likely from your crushed coral bed and very small skimmer for this load and size tank. Please consider upgrading your skimmer to something designed for your size tank and of high efficiency. (Aqua-C or Euro-Reef are favorites, check out our WetWebMedia sponsors). The CPR is maxed out at about 70 gallons. With this number of fish it's overloaded.> Also right now I use a gravel vac during my water changes but with the sand how should that be maintained. <Detritivores, snails, hermits, etc. Be mindful of fish predation on some types of detritivores (shrimp and crabs) and stock accordingly. Disturbing a sand bed interferes with the bacteria, pods, life forms that do the dirty work, it is not usually necessary to vacuum. A small powerhead works to periodically "stir" detritus into the water column where it can be filtered out. Please pay special attention to your filters and clean the sponges/media regularly (in used tank water) to avoid nitrate build-up. The sand and clean-up crew do most of your work on the substrate.>  Your thoughts are greatly appreciated. Thanks for your most valuable time, Gene Lotardo PS. Maybe 40ppm nitrates is not so bad..... <Nah, you don't want that! The alternative is too easy to achieve! I would go for it. DO watch your water quality after switching or switch partial amounts over a week or so. If your amm/nitrites peak, perform water changes until the sand catches up. Usually not a problem, maybe a small amt. of ammonia with this new sand. Test, test, test, and change if needed. Good luck! Craig>

Nitrate Rising Hello! <Good evening! Scott F. with you!> I enjoy your web site and love the Q&As. My wife and I started a reef tank almost a year ago and all is mostly well. The one problem we have been fighting is high nitrates. Readings jump to 40 - 60 ppm just a few days after a water change. I have removed the canister filter we were using since I was worried that it could be acting as a nitrate factory even though I clean it every 7 to 10 days. I feed the fish a very small amount of food once each day. I have read much about nitrates on this site as well as others and in some very good books, but I am still stumped. The tank setup is a 37 gal, 70lbs of live rock, live sand, 2 Ocellaris Clowns, Coral Beauty, Six line Wrasse, Yellow-tail Blue Damsel, Neon Goby, various mushrooms, Brain Coral, Star plops, 2 Bubble Tip Anemones, 2 serpent stars, snails, and crabs. We also use an Aqua-C hang on protein skimmer. I am thinking on adding a sump just to get the heater and powerhead out of the tank for a cleaner look and will be moving to an in sump skimmer. Any suggestions? Is the bio load in the tank to high? Thanks for your insight. -Bryan <Ok, Bryan, lets touch on a few things that could make a difference. First, your tank is, as you may have suspected, at about the upper end of its fish capacity. You seem to be a careful feeder, and that's good. Don't add any more fish! Your idea of adding a sump is a good one, as it will not only give you space for a bigger skimmer, but it will add to your system's total water volume. As Anthony likes to say, "Dilution is the solution to pollution"! Speaking of dilution- how often do you perform water changes? Try smaller (5% or so) changes twice weekly. Siphon as much detritus as you can. And, check your source water. If your starting with tap water that has 10+ppm nitrate, that's a contributing factor, too. Maybe time to look into an RO unit? Your skimmer is one of the best hang-on units around, but make sure that it's pulling a cup of that yucky stuff out at least a few times a week-and clean the skimmer often, as the drying organic product will impede waste collection (sort of a vicious cycle, huh?). Do consider a deeper sand bed (3 inches plus), as natural denitrification is more effective in a deeper sand bed. Finally, consider growing some macroalgae in a lighted portion of your sump (when you get one), and harvest it regularly and religiously. Avoid Caulerpa- try macroalgae like Chaetomorpha or even Halimeda. These algae do utilize excess nutrients (nitrate among them), and can have noticeable impact on nitrate when maintained in suitable quantities and harvested. Well- I hope I gave you a few avenues to explore to help resolve your nitrate problems. Make use of the great resources we have on the wetwebmedia.com site. I know you'll be successful! Good luck!>

Tonga rock - Nitrate control To the always helpful crew at WWM: <Howdy.. and thanks kindly> I currently have a heavily stocked (Craig has already reminded me of this)110 gal fish only tank that I am in the process of removing the crushed coral substrate <a good move> and will be replacing it with Carib-Sea's Arag- Live Special Grade Sand and Carib- Sea's Bermuda Pink Sand (3bags Arag-Alive 1 bag Bermuda Pink). <save your money on so-called "live" products unless you like it purely for aesthetics. A less expensive, more attractive sand (if another suits you) can become more live from a single inoculation of real live sand from a reef tank/LFS in 2 weeks. The whole "live" sand in a packed bag is quite shameless marketing IMO. Technically, any product not sterilized and hermetically sealed is "live" with bacteria. Ha! What a crock> I think this should give me a depth of  about 1 1/2".... for now. <whoa! You will want thicker or thinner but not in between 1/2" and 3". Not deep enough for nitrate reduction, but too deep for nitrification. Likely to become a nutrient sink instead> (maybe I should have a deeper bed?) <OH Ya! Nitrate reduction begins around 3" but aragonite has a half life of around 18 months... so a 3" bed begins to dissolve and weaken from go... hence, start with at least 4-5 inches and enjoy a fine natural nitrate reducing vehicle> Now for my question...I was also thinking of removing the coral rock (not live) that has been in the tank for 3 years. I am not sure how many pounds it is but it displaces about 25 gallons of water...some  large and heavy pieces. I was thinking of going to Tonga branches. I was wondering if the Tonga branches can/will perform the same function as Fiji rock. <not even close. Branch rock is attractive to me, but the fact is that it is not porous Fiji rock but simply dense and encrusted Acroporid skeletons (corallums). Really weak for a biological filter but quite attractive, again, and adequate for very light bio-loads> My local store currently has both fully cured.  I primarily used the coral rock to make various caves etc in order for the fish to feel secure. I'm thinking the Tonga will give me same effect with a lot less water displacement, <agreed> and get the benefits of having some live rock in the tank to assist in nitrate reduction. <live rock of any kind is weak for nitrate reduction... you need huge rocks for that to occur. Deep live sand is much more effective at nitrate reduction> Will the change over really help with my  water quality or should I consider saving the additional expense and just keep what I have? <if deep sand and/or porous live rock are not options then stay where you are with the mature stable substrate that you have> Your thoughts are greatly appreciated. Thanks, Gene <best regards, Anthony>

Reducing Nitrates (Pt. 2) Scott, Thanks for the tips! I had not thought about the sump increasing the water volume.  <An often overlooked benefit of sumps!> I will add to the sand base since it is only about 1.5 - 2 ". Any recommendations on good in sump skimmers?  <Well- since you have an Aqua C already, why not try one of their in-sump models? Good stuff!> Have been thinking about an RO unit as well since I have been buying RO DI water from the local grocery store. No more fish. <g> We would just like to add some more polyps or Xenia once the nitrates are under control. <Yep- that should be okay> Thanks again! <You're welcome. I'm really glad I could help! Let us know if we can be of further assistance! Good Luck! Scott F.> -Bryan

Re: Tonga rock - Nitrate control Anthony: Thank you for your quick and informative reply. <my pleasure> A couple of minor questions and points before I move on. I want to make sure having a deep sand bed will be ok with a heavy fish load. <indeed... not always so. It requires very strong water movement and dedication to aggressive nutrient export. This means have one or two wicked quality skimmers (no red sea, SeaClone, prism, Kent stuff here :) ) that actually produce daily skimmate with ease and consistency> If so, I will add more sand to give me the 4" depth and remove the coral rock I have in there now. Additionally, I will use the Tonga branch for mostly decorative purposes and also to create various "ins and outs" for the fish to feel secure. <agreed... cool> I think the Tonga will also help increase the effectiveness of the sand bed because I can place it in away that will leave most of the sand be exposed (greater surface area) rather than using rock which will cover a lot of the sand bed. <very good point. Agreed> My final thoughts are: 1) Use deep sand bed to help with water quality, nitrate reduction, etc <easily achieved> 2) Eliminate large coral rocks to increase actual gallons of water in the tank from reduced displacement. I can probably gain about 20 more gallons back. <a minor concern or help > 3) Use Tonga branches to break viewing lines, create caves and hiding places etc to reduce any stress on the fish. What do you think? Gene <very cool>  PS. I have used your web site many times to research various topics and have submitted a couple of questions. It's a true pleasure to have you guys to turn to! <its a labor of love... and thank you, my friend. Anthony>

Nitrates and help with Mad-Clown Can't believe how much I have learnt since I have found your web-site. I thought I had eased myself in to the hobby with reading about it for 6 months / hovering around LFS's etc.. before laying out my cash. Disappointingly, I have found that my LFS's give conflicting advice and with retrospect am dubious of the set-up I have been sold. However, to date (the tank has been set-up for 8 months) I have a 55g tank with approx 60Ib's of live rock and some soft corals. All readings are ok with the only concern being a nitrate fluctuation that creeps up to 10ppm (normally about 5ppm). For filtration I have 1 internal filter (PolyFilter & carbon), 1 external Fluval 404 with half the chambers containing biological media, a quarter containing the Kent Nitrate reducing product and the last chamber containing filter floss. My question is, is the bio-media in the Fluval doing any good? It always looks so clean, should I replace this with something else (bearing in mind the live rock)? <I would chuck the biomedia altogether and use nothing but carbon, changed regularly. I suspect your biomedia is the source of your nitrates. Increase LR and live sand to naturally reduce nitrates.> I use a Prizm skimmer which I find works quite well (dark gunk coming out!). Additional water movement is made by 2 internal mini-jets. Turnover should be ten to twenty times tank volume. IOW, for a 55, 550 GPH (minimum) total for all the powerheads.> I have some soft corals in the tank that have grown and look incredibly healthy and to date the only casualty has been a snail, which just seemed to have disappeared! The fish in the tank are: - 2 Ocellaris Clown (1in and 1.5in) - 1 Bi-Colour Angel (3 inches) - 1 Orange Stripe Prawn Goby (2 inches) - 1 Yellow Tang (4 inches) Besides the questions concerning the filtration above, I would really appreciate your help with the below: - Do I need to supplement the oxygen from the skimmer with an additional air stone? <No. If it's cleaning dark skimmate it's fine.> - The yellow tang is a new addition and has just come out of quarantine. He has been in the tank now for 48hrs. However, the larger clown has taken a strong dis-like to it and it tormenting it non -stop. The poor tang (a giant beside the clown) is cowering under a rock and will not feed (feeding fine in quarantine) <Re-arrange the clowns digs some to throw him/her off and add some well cycled live rock. This will change territories and add to your nitrate reduction capacity while removing the biomedia from the Fluval, etc.> - Any additional advice on keeping the nitrates down. <Less nitrifying outside biomedia and more natural de-nitrifying LR and LS.  Regular cleaning of sponges, any other filters.> I have a Aquamedic R/O unit at home and do regular 15% water changes every week. The sand base is just under an inch and is vacuumed / disturbed once a week using a Eheim device which doesn't suck in sand. Look forward to your responses. Bill <Ah....stop this, add more LS, (slowly over days), get some  detritivores to keep your sand in shape....stop vacuuming, it disrupts the natural sand processes, even in thin sand beds. Your thin sand bed could also be nitrate source, especially with disruption. Should be fine with enough rock or by adding more LS. Hope this helps!  Craig>  

Nitrate reduction Well, Anthony. here I am again, making my self perhaps a little tiring, but the fact is that the more I read about our hobby, the more I realize that my knowledge is really poor... <not poor at all, just "young"... we learn every day. Gandhi is quoted as having said (to paraphrase)... live like you will die tomorrow and learn like you will live forever> My nitrates are stable at 100, going a little down with the water changes. My tank is FO for the moment, but still I know that reducing the nitrates would mean a lot for the health of my fishes.  <yes... agreed> On the other hand I am very attracted to crustaceans (shrimps, etc) , which need 0 nitrates (?). So, I have been reading in your site about the several ways to reduce them. After all this reading I have come up with the following questions: What is the best in my case? - Buy live rock? Has the live rock any kind of problem with the existence of wet-dry filter that I am planning to buy? Should I buy it after I drop the nitrate or before? <this will help the system in many ways and is highly recommended...however, it will not significantly reduce nitrates> - Make a deep sand bed ? (6 '' +) ? Only with one material - fine aragonite sand? How can I have "live sand"? Do I buy it ready "live" or the fine aragonite sand turns to be "live" by itself after some time ? <yes... the best solution! you can get dry sand at 4-6" or more depth and add just a little bit of live sand (a handful literally would be fine) or live rock to seed it. It will all become biologically live in a few weeks> - Buy a denitrator? <expensive and laborious... hold off on this if we can manage fine with only the deep sand bed> Please do not bother to give long answers, cause you see I have placed too many questions. You can answer only with a yes or no, or just the right thing I should do, just to give me the direction in which I should move. Thanks REALLY and please forgive my grammatical or syntactic mistakes, I hope you understand the meaning of my sentences. Regards, Thanassis...Greece <no worries at all my friend. We are pleased to be able too help. And your command of written English is actually very good. I understand you perfectly each time! Best regards, Anthony>

Nitrate Removal Hi Bob (or whoever), <Hello> I have written to you before regarding a v'small marine tank I had setup, which may I say was very successful indeed. I have now converted my brackish tropical tank to full marine (after removing any fish that wouldn't tolerate a full salt mix). I am trying to use the same method in which I succeeded in with the v'small tank i.e. not interfering with it as much as possible. <Good approach> Before with the v'small tank the only thing I ever did was top up the water and feed tiny scraps of food for the corals and for the blenny (excellent suggestion you made to get one for algae clearance, not a lawnmower type but sufficient). My next question is this: Now the 2 foot tank has been converted and has all the coralline contents of the v'small tank I am having a problem, the no. of fish (approx 1/2 pound of fish poss. a bit more very excessive for a tank this size, minimum feeding though) in this tank now outweighs the amount on nitrate the rock can accommodate. Currently there is 0% ammonia 0% nitrite and the tank has been cycled for ages, using the method as before I do not wish to constantly cycle the water to remove nitrate and other such toxins, please tell me which of the following would be the most natural way of reducing nitrates (and other possible toxics and poss. introduce some trace and calciferous elements). I would like to emulate nature as much as possible (i.e.. not use protein skimmers and chemicals). should I use 1. a live sand bed (along with all the setup difficulties) with slow trickle feed and plenty anaerobic bacteria (possibly in separate 12x10x10 tank full of sand). or 2. a v'slow trickle filter filled with a material that will support anaerobic bacteria. <Mmm, in order, the above... I'd use 1, then 2, then 3... or perhaps all three. Please read here: http://www.wetwebmedia.com/nitratesmar.htm for my expose on nitrates in marine systems... and the many FAQs linked. Bob Fenner> Thanks in advance Alex. (Sandgate, Kent, UK)

Nitrates We have a 75 gallon salt tank that we have never been able to get the Nitrates down to a reasonable level on. They are always around 80 or higher even with water changes, a protein skimmer and 2 filtration systems. We did take the bio balls out of the one system on the advice of a student in marine biology. We have 4 fish in the tank. A sail fin tang, yellow tang, a damsel and a sand sifter goby. Also a snail. We have about 40 lbs of live rock. Any suggestions? <<Greetings, Susan. My suggestion would be to double your quantity of live rock, and if possible triple it and jam the excess into your sump. Live rock is probably the best solution out there for natural nitrate reduction.>> Susan <<Cheers, J -- >>

Nitrates and other misc. ramblings Hello everyone, hope all is fine. <<And I hope all is well with you.>> I have been thinking about nitrates, since my predator tank always reads high, and how to reduce them. In a sump, say a 30 gal, would a deep sand bed or live rock be a better reducer of nitrates? <<How about both?>> Would this type of sump reduce nitrates? <<Not on day one, but over time, it would certainly help.>> Also if a tank has a high nitrate level and all the fish are removed, will the live rock eventually reduce the nitrates to 0.0 without any water changes? <<With a couple of other qualifiers, yes... high nitrates can have as much to with how you feed, as it does the fish you keep, which can influence how you feed - see the cycle here?>> If yes, does this process take a long time? (days -- weeks -- months)? <<I'd give it a month or so.>>  New subject; when preparing new water for water changes I use a water conditioner like Stress Coat or Start Right. <<Ok.>> I believe the main thing the conditioners remove is chlorine. <<Some also add chemicals to induce mucus production to help the fish's slime coat, others include other top secret ingredients... depends on the brand.>> Doesn't chlorine evaporate quickly from the water while it stands with an air stone for 24 hours and then another 24 to 48 hours with the salt mix? <<Something like that, yes.>> If it does, is it really necessary to use water conditioners as long as the new water is aged? <<Ah ha! You've just made an important connection - no bottled solutions required.>> Thanks in advance for the help. And I do realize the real answer to my questions is I need a bigger tank, more water volume, and/or fewer less hungry fish and better/more consistent tank maintenance. But I'm always looking for an easier less costly way to keep my fish and continue to find out there are no real short cuts. <<Nope, no real short cuts at all... Cheers, J -- >>

Adding Siporax/ceramic beads in the sump to lower nitrates. Bob, I don't get it. Aren't bioballs the same thing as ceramic beads?? <No... one principally favors aerobes (the plastic two dimensional materials called "bio-balls" et al... the other harbors anaerobes... is three dimensional... entirely opposite reaction series> In your Nitrate FAQ. You recommend adding ceramic media in the sump to lower nitrates. Aren't ceramic media the same as bio balls?? <You're repeating yourself.> Aren't they both suppose to both harbor beneficial bacteria? <Ah! Yes> In your articles you say remove the bioballs. Isn't adding more ceramic media defeating this purpose? Please explain. <Keep studying my friend. Perhaps a complete book on the marine aquarium hobby... Like Baensch' Marine Atlas v.1... Bob Fenner> Linstun

Ceramic media Reading your FAQ in the nitrate section. I have added some ceramic media in my sump to try and lower my nitrates. I have a 240 go FO system, wet dry filter/bioballs. Should I turn off my ozonizer, skimmer and UV sterilizer so that my new ceramic media can colonize bacteria? Or is it ok to leave all of my equipment on? <Just leave all this gear on... the new media will be inoculated, populated soon enough... and the benefits of running all these mechanicals far outweigh anything you might get by shutting them off. Bob Fenner> Linstun

Saltwater Nitrate reactor Bob I have a 100 gallon three feet high style saltwater tank. I have been into the hobby for 5+ years. I have been very successful with my fish. I do regular water changes 1/3 ever 30 days, and clean 40 % of the Coral and vac the coral gravel each time I do a water change. I consider myself well educated the hobby . My fish have great Coral cover ( fish only ) and I feed them a variety of foods . I don't over feed them. They get Broccoli & Parsley for constant gracing and one leaf of lettuce am only. Evenings I alternate flake, meat, sponge, etc..... Now onto the problem which might not me a problem but it has always bothered me. I can not get the nitrate ( red ) down to a orange / yellow level........My fish are all very health, have good color. Water temp 79.8 / UV / wet /Dry with Fathom Skimmer & CPR back pack, little Giant 1240 flow, Azoo temp control, two 48 inch top lights, one 100 % Actinic with cooling fan and the other 100 % Daylight. There are two power heads inside lower corner, one only runs after evening feeding to remove excessive flake etc. both shut down 10 pm until 8 am to allow fish time to sleep.......Lights on timer and tanks 4 years old. French Angle , Imperator Angle changing 20 % , Power Blue Tang, 2 Coral Beauties, Foxface, Honeycomb Puffer, Yellow Tang, Humu Trigger, 2 Gold Band Clowns, Blue Regal, Sail Desjardin Red Sea. These fish have been in tank only 5 months. However I had the exact same fish for three years. We turn off the pumps prior to evening feeding. I travel and my wife and kids helps feed, one night they forgot to turn the tank back on next morning I lost all my fish except the Huma Huma. Very very sad........ <Yes> Now my question : I have been considering installing a Nitrate Reactor......will it work and reduce the Nitrate levels ???........I want my fish to have the very best environment I can provide but I don't need to buy something that's not effective. Also the true story on the maintenance of the Reactor......... I enjoy reading your responses and articles many of which have helped me become a better fish keeper......... Thank you..........Bill Culver <Ah, a pleasure to serve. There are nitrate reduction tools on the market that can/do work... Most are anaerobic/hypoxic bacterial culture facilities that require (IMO too much) testing, adding of sugar, alcohol... other feeder stock. Some electric, electronic devices are out there too... For such a size, type system as yours and the good, regular maintenance you perform, I would put my money, time into either a Deep Sand Bed/Plenum and/or an external sump/refugium with live rock, lighting, macro algae set-up to reduce nitrates (along with many other benefits). Some input on both ideas can be found in various places on our site (www.WetWebMedia.com). Please start here: http://www.wetwebmedia.com/dsbfaqs.htm http://wetwebmedia.com/Plenums.htm http://wetwebmedia.com/no3probfaqs.htm and the links/FAQs beyond to formulate your plan of action. The pre-made denitrators on the market are not worth the money... and the approaches mentioned are far more steady, beneficial in action.  Bob Fenner>

Natural Nitrate Reduction in a "messy" FO tank. Bob, Anthony or Steven... <Steven this morning.> Hello there. I think that my question I emailed in may have gotten lost, because for the first time, I got no response. I'm assuming it wasn't deliberate. :-) So here it comes again... <Definitely not deliberate.> Anyhow, let me start out with my current setup. I have a 100 Gallon FOWLR tank that is plumbed to a 40G Rubbermaid sump that holds a Turboflotor 1000 skimmer. I have 1" of LS for aesthetics in the main tank that I'm considering reducing down to 1/2" from what I've been reading on the site. I just added 35lbs of LR to the existing 80lbs, for a total of 115lbs of Fiji LR. The tanks inhabitants are: Naso lituratus - Naso Tang - 5.5" Rhinecanthus aculeatus - Picasso Trigger - 3.5" Balistoides conspicillum - Clown Trigger - 3.5" Premnas biaculeatus - Maroon Clown - 1.5" Diodon holocanthus Linnaeus - Porcupine Puffer - 3.5" Now that we've got that out of the way... here are my questions. My main goal is better nitrate removal because they are over 70 right now, and I know I can do better, even if my fish are of the "messy" variety. 1) I want to add in another 18G Rubbermaid container, slightly higher than the sump. I would pump in water from the sump via a small RIO 800 and let it flow back via gravity into the sump, in a mini loop. What would you suggest I put in there? <Two options: very DSB (almost all the way to the top) or the Ecosystem method.> Can I get enough mud in a 18G container to make a difference? <Will have some impact though hard to measure with standard test kits.> I know I should have 20-30 lbs of Miracle Mud or the new Kent product, but what's more important, surface area of the mud or just shear quantity? Caulerpa? Both? <All of the above.> 2) Are the benefits of Caulerpa (nitrate reduction and refugium functions) great enough to outweigh the possible problems of it going "sexual" and possibly damaging the tank? <Allegedly the 24/7 lighting cycle makes going sexual less of a potential problem.> I've tried Caulerpa once before, and it was hard to keep alive. <Needs adequate lighting and nutrients, which you have in abundance.> 3) Should I convert my sump (which only holds water, heater, return pump and skimmer right now) to a 4" DSB? <I would not do this over adding the second vessel.> Will the surface area of the Rubbermaid 40G container be enough to help reduce nitrates in my 100G tank? <Again, hard to say how much the exact effect would be. It would do something, but hard to quantify.> Someone mentioned in an earlier email, that perhaps a DSB wouldn't be the best way to go in a FO system with such messy eaters, and that it can become overwhelmed. <That was me and is still a possibility.> How long does a DSB take to establish before I can notice nitrate reduction? <Probably at least one month or more.> 4) Should I just give up on natural nitrate reduction and face the fact that with such messy fish I'm gonna have to do a lot of frequent water changes? <Probably a better option. Do be sure that your skimmer is filling its collection cup at least several times weekly. If not clean the pump out and run it in some vinegar water to remove deposits. This is a much overlooked aspect of husbandry, skimmer pump maintenance. You may also want to consider a RO unit to limit nitrate and other contaminants from coming in with your source water. If you plan on making frequent water changes, make it easy on yourself. The easier it is the more likely the changes will get done. RO water into a large Rubbermaid garbage can, aerated, heated, and mixed with salt. Python or other device to drain water into a floor drain or toilet. Pump water from garbage can back to tank, no hauling buckets.> Thanks in advance... <Hope this email finds you this time. -Steven Pro>

Nitrates I'm having trouble keeping the nitrates down (they are very high) in my 55gal. It's been set up for about a year now. I'm doing a 5gal water change every two weeks and adding CombiSan. The mid Blue face angel-Purple Tang- & small Imperator <These fish species are mis-placed here... all/each needs more volume than a 55>  seem to be doing fine but I'm sure they would be happier if the nitrates where down. I've tried adding Chem-pure with no success..........HELP.......Lou >> The Chemipure and CombiSan will do little to nothing to effect the nitrate condition in your system... You can (and should) approach nitrate control from the angles of limiting production and eliminating it through biological uptake: Do you have wet-dry media? A fluidized bed filter? These are nitrate factories by themselves. Do you have any live rock, macro-algae, room for putting in a denitrating sand bed or algae-mud filter in a sump? These are some of the best "nitrate users"... Bob Fenner, who says (as usual), "how high is high?"

The 160 is reading 80ppm for nitrates I have two tanks, one 160 (fish only), and one 55 (reef). The 160 is reading 80ppm for nitrates, even with Chemi pure in the sump, and the 55 is reading about 50ppm, way to high for inverts. I have been doing water changes once a week, at about a 30% replenishment rate for each month. Should I increase the amount of water changed, and/ or are there any truly reliable products (reactors or sponges) that can eliminate this stress to the tanks? While I am at it, is Maracyn safe for treating infections with out harming the denitrifying bacteria? Thanks, Tom Griffith >> Do look into more "biological means" of addressing your nitrate concentrations/excess... Do you have much in the way of live rock, macro-algae... have you considered setting up a natural nitrate reduction area... maybe in a sump... with some Caulerpa algae and a light even? Where are your excess nitrates originating? Do you have plastic wet-dry media, a fluidized bed filter? Overfeeding highly-proteinaceous foods? No to larger water changes, and the use of chemical filtrants for this purpose (lowering nitrates). And Maracyn (tm), erythromycin won't harm nitrifying bacteria. Bob Fenner

Siporax Bob- A couple of weeks ago, you mentioned a product called Siporax. What is it, is it worth getting, and how much do you use? <Search WWM for this sintered glass bead filter media and its applications> What do you recommend for a check valve for the return from the sump? Thanks. <If you can, no check valve at all... Just an "air break" at the discharge point to disallow back siphoning... If your return is drilled and discharges through the bottom... and you have to have a check valve, my favorite in order are "Ball", then "Spring/plastic", then lastly "Swing" types. (an article about these, and some images posted?, maybe not yet, under the "Pond Article Index" at my www.wetwebmedia.com site> Andy Lange PS. I did end up tearing down my tank after the mysterious prolonged dying of fish, you helped me with. The 'new' tank recently 'popped' and I will try again. >> <Ah, good to hear... probably best. Good luck my friend in fish, Bob Fenner>

Question... why high NO3? I recently purchased around 40lbs of rock, got 15lbs on a Tuesday, stuck it in the tank, and another 25lbs the next Tuesday, stuck it in the tank. I was under the impression it was cured, but now am not so sure.  <I am... it's not... entirely... but on its way> My ammonia levels are zero and have always remained at zero. Somewhere along the line, probably before the rock, my nitrates level went high, like around 80ppm. Now, they will not come down. <They will... patience> I have a skimmer and have changed water, several times, no effect. I think the skimmer made them come down a tad, but not too much. I did around a 25% water change today, and removed probably 15lbs of rock or so,  <Why?> and I got them down to somewhere around 40-60ppm. My tank has been set up since Dec. 26 of 1999 and everything seems to be doing great and seems very healthy. I have lots of inverts and have put fish and inverts in the tank with the high nitrates. I was told they wouldn't survive, but everything seems fine. I'm puzzled,  <I'm not... and you "just" have to wait... do nothing and your "nitrate problem" will cure itself... and become very clear to you> FFExpress is puzzled, other people I have talked to are puzzled on why everything seems to be ok with the high nitrates. Now, could my test kit be wrong, or something, what is going on here?  <Nothing wrong here... your tests are likely accurate... time needs to go by... the animals you have are bio-acclimated to nitrates and tolerant otherwise (the damsels)... wait another month... without changing water, moving your rock...> Why won't my nitrates come down and why is everything so healthy if my nitrates are high.  HELP!! >> No help necessary... relax and enjoy your system Bob Fenner

Anemone & Nitrates in a saltwater tank I have a 75 gallon saltwater reef tank, with a tidepool trickle filter, large skimmer and 2 florescent lights. We have 2 sleeper gobies, 1 yellow tang, 1 yellow tailed blue tang, 1 flame angelfish, 1 coral beauty angelfish, 3 green Chromis, 1 skunk shrimp, 1 fire shrimp, 1 clam, 1 Condy anemone and 1 Haitian anemone. One of my questions is - I have a problem with Nitrates, it never falls below 80, I never have ammonia or nitrites, but I do have Nitrates. I do a 12 - 15 gallon water change twice a month. I add nitrate reducer, but the nitrates never go down. I do have live rock in the tank, approx 60 pounds - I feed the fish 1 cube of bloodworms and 1/2 cube of Formula 1 and 1/2 cube of the green formula daily. The Tangs get a small piece of seaweed daily as well. I feed the anemone's a very small piece of shrimp twice a week each.  Any suggestions? <To reduce the nitrates? Sure. Remove the "wheel" <the principal cause>, to reduce/use up the nitrates: add some macroalgae to your system, increase the amount of live rock, add some anaerobic media to your sump (Siporax Beads, Ceramic like Eheim's Ehfi-Mech), attach a better skimmer, increase your lighting intensity, duration.> The other question is - the Haitian anemone is supposed to be pure white with a bright orange/pink bottom - he appears dirty - the Condy also appears  dirty - why? <Water quality> I have recently lost 1 Condy anemone - but I thought that might be due to the Urchin that was in the tank, the urchin appeared to be picking on that particular anemone - the urchin has since been executed. He was neat until he started picking on the other inhabitants I would appreciate any suggestions that you can give me.  Thank You, Annette >> And I appreciate your participation in this forum, thank you. Be chatting, Bob Fenner, who offers further explanation of the above terms, concepts... posted in articles and more at the site: www.wetwebmedia.com

Nitrate I recently lost a finger coral and my mushrooms constantly stay shriveled. I found a high level of nitrate in my system. I have been doing about a 20 percent water change about every 2 days. The nitrate seems to be gradually dropping. I added some Nitra-sorb to my sump. Will doing this much water changing effect my system and what other suggestions would you have to lower my nitrate and keep it low? I have a 125 gallon tank with about 150 pounds of live rock a 2 inch sand bed, a 20 gallon sump with bio-balls and an AMiracle protein skimmer which is air driven and rated at 130 gallons, all lighting is VHO. >> Hmm, a very common complaint... with the usual lack of key information... Just how much is a lot of nitrate? Do agree with you re the probable cause of problems here... metabolite accumulation... as detected and pinned on the nitrate reading (whatever it is/was)... and lots of ways to rectify the situation: Let's briefly state them and refer you to more detail: 1) Remove the plastic bio-balls from the sump... They're driving nitrification too much, too fast... they're the direct cause of the nitrate over production. 2) Spiff up, upgrade your skimmer. Make cleaning the contact chamber, skimmer cup part of your monthly maintenance regimen... If the skimmer is too puny, look into a better, more efficient one (a needle-wheel type like a Turboflotor in your skimmer is what I'd use). 3) Look into the benefits of culturing some purposeful macro-algae, either in the main tank out of the way, or in a/the sump... with a light on continuously or in a alternating light cycle with your main system... Some Caulerpa and/or Halimeda would work wonders. 4) How about building a plenum or adding some anaerobic filter media to your/another sump? Siporax beads, ceramic filter media really help speed up the "opposite" rate of denitrification... getting rid of the nitrates naturally... 5) How about speeding up the use of the rate of nitrate uptake with your present photosynthetic life? By increasing (duration, intensity) lighting? Are your lamps still within their useful lifespan?  Please do take a look at the growing mass of literary materials on these aspects of water quality improvement stored at the site: www.wetwebmedia.com Bob Fenner<<

Nitrate factory Hi Bob, I've noticed that you are not a big fan of "trickle filters," stating that they are a nitrate factory. What is your opinion of the "bio-wheel?" Isn't that the same type of effect as a trickle filter? Are they also considered a nitrate factory? Thank again for your excellent advise and your daily Q&A - you've helped me tremendously. >> Yes, both wet-dry media and the type of wet-dry media called "wheels" over-drive nitrification. In the absence of sufficient nitrate-using life, anaerobic media (live rock, plenums, Siporax Beads, Ehfi-Mech... ) they can/do cause accumulated/ing nitrate anomalies. Bob Fenner

Nitrate reduction.... Hi Bob, I have had my 40gal tank running for a few months now, with about 45lb or LR, a CRP Bak-Pak 2 skimmer (with the bio-bale removed) and a Fluval 303 canister filter. I recently reduced feeing to once every other day in an effort to lower nitrates, they have come down to 5ppm (from 10ppm) in the past week. (I also did a 10% water change)  I've been reading a bit on refugiums as a good source of natural nitrate reduction, and was considering adding one to the tank with the intention of (eventually) removing the 303. Is this wise ? thanks, Rich. >> <Possibly to most assuredly. Would add a refugium, with maybe an anaerobic deep sand bed area, or at least live rock and probably Caulerpa or Halimeda genera macro-algae... and either alternate lighting cycle fluorescents or continuously on. Please take a look through some of the particulars and specific q and a's on refugiums, sumps, plenums... stored on our site: Home Page  Bob Fenner

Nitrate filter hello Robert I have purchased a Coralife denitrator that is connected to a canister filter I ran it flat out for 24 hrs and left it shut off for 3 wks the nitrates exiting went up to 100ppm then decreased to 10ppm I opened the drip valve to 2 drips per min the next day checked nitrates back up to 100ppm this has happened twice HELP. KEN. <Help with? These types of "anaerobic box" Denitrators are finicky... requiring steady feeding of carbon (usually a sugar prep. solution) and are definitely NOT reliable... I have consistently NOT endorsed their use for more than three decades of writing for the pet-fish hobby and business press... Would encourage you to rig such a device (if using at all) to (in/out) of a separate sump/refugium with live rock, macroalgae, lighting of its own... and possibly a plenum type situation there... to afford you some greater measure of control, safety from nitrate swings. Bob Fenner>

Nitrate Filter Questions Hi Bob, Thanks so much for sharing your knowledge and life's work both on-line and in the Conscientious Marine Aquarist. I've found your site to be a wealth of knowledge and I frequent the Salt Water Fishes section. <Ah, very gratifying. Exactly what we desire> I have a large 280 Gallon Fish only Marine Aquarium that I built modeled after GARF's Do it yourself instructions. I have a large DIY Wet/Dry, Skimmer, and Nitrate filter w/ a 30 watt Aquanetics UV Filter. My question relates to the Nitrate filter. After a little research and understanding of what I would be able to reasonably maintain, I decided to try a Coil nitrate filter similar to the one described on the following URL: http://saltaquarium.about.com/pets/saltaquarium/gi/dynamic/offsite.htm?site= http://www.aloha.net/%7Ehqf/indexdondenitrator.htm <Yes, am familiar with these designs> I have the input of the Nitrate filter connected partially to the output of the U/V filter. I left the U/V filter off for a day in case it was needed to 'Seed" the Nitrite filter w/ bacteria. It's been about 2+ months of dripping and I have found that the output of the nitrate filter shows the following: Slow Drip rates: Ammonia = 0, Nitrites = 5ppm+, Nitrates = 5ppm ish Extremely Fast Drip Rates: Ammonia = 0, Nitrites = 0, Nitrates = 60ppm <Okay> I understand that in the second case that I am not creating the anaerobic conditions to decompose Nitrates. However, in the first processes I find that the colors of the Nitrates test by AQ.. PHARM results in colors that are slightly off from the color chart, but they nonetheless result in colors similar to the 5ppm color range. <Yes, don't let this throw you... some nitrites produced and an artifact of the test kit itself> my question is as follows: Specifically, which strains of bacteria become anaerobic and decompose nitrates?  <Hmm, not "become" but "ones that live/proliferate in the environment of your making which is hypoxic (oxygen limited)... "Nitrobacters", others...> Are these the same as the Ones that are involved in the conversion of Ammonia to Nitrites? or the ones that decompose nitrites to nitrates? Or Neither? <Neither> Can you hypothesize why I might be getting high nitrites?  <A few possibilities come to mind... bacterial and other microbial digestion/predation going on the surfaces of the "coil" areas... most likely> The quantity doesn't bother due to the size of the tank and effectiveness of main wet/dry filter. Nonetheless, I ask because I am wondering if I should speed up the drip process and develop a strong colony of bacteria, similar to a wet/dry, and then slow it back down. Any comments you have would be much appreciated. Sincerely, Jeff <Best to disengage the UV from this pathway, slow the drip down to just that... a few drops per minute... and leave it all as that... Do investigate other (in all frankness vastly superior) methods of encouraging denitrification, use of nitrates... deep sand beds (best in a sump/refugium) w/ or w/o a dead space/plenum, use/culture of live macro-algae... somewhat touched on in "Nitrate" FAQs and elsewhere on the site: www.WetWebMedia.com Bob Fenner>

Re: Some questions about reefs (Eheim Wet-Dries, overflow mechanisms...) Hi Bob, Today I accidentally ran the Eheim filter dry while I was siphoning water out of the sump. I did not notice that the filter was running dry for over and hour and by then it was too late. I will buy a new Eheim wet/dry filter tomorrow. I hope fish will be okay over night while I get the new Eheim wet/dry filter. Which one is the best one for me to get? <Actually... I don't care for Eheim wet-dry filters... would just use one of their canisters... the bigger the better> After I did this I was so upset that I installed an on/off switch in the sump area which switches everything off in the sump. Now when I need to do something, everything goes off and there is no risk that this will happen again. <Good idea> I have also decided to replace the tank with one that has an overflow built in. The hang-on overflow has lost it siphon once and water start dripping out the top of the tank. Not a funny thing when this happens.  <Decidedly not... built-in overflows are better... more reliable... though not fool-proof either.> Now I check the overflow every day. I have ordered another 6 foot tank, but this one is going to be 2 inches taller and give me another 12 gals of water volume. So after the tank gets delivered, hopefully in a weeks time, I will move everything into the new tank and retire the old one. Is there anything I should know about, when moving everything over to the new tank? <Not too much... please see the notes on "Moving Aquariums" posted on the www.WetWebMedia.com site... The same as replacing a tank.> I purchased 3 green chromes fish and they are great! They eat everything I put in the fish tank. I had to train them at first but now they come running over when the lid goes up and they wait for the food to fall down into the water. My cleaner shrimp just molted and has come back out to play after about 3 days (which was today). I was concerned that he was dying when he disappeared, but I'm happy to say he has not. I also found his malted shell. <Yes... leave it in there a week or so... this animal may ingest it in part... to make its new exoskeleton... it won't pollute your water.> I measured nitrates and they are up around the 5ppm. The algae just keeps growing. I have read the information on your site and I will try a few of these. I do have some questions about some of the things I have read else where. What one person has done to lower nitrates is to dose sugar water into his sump. About 1 table spoon is mixed into 1 gal of water and then slowly dosed into the sump over a period of about 12 hours. The nitrates go down to 0 after dosing but when they come up again, he repeats the dosing. I have found many references to people doing this. Do you know about this? <Yes... these carbohydrate additions boost denitrification... can't be done continuously... and some downsides... potential filamentous algae profusion... which you can see happening> What do you think about doing this? I have also read many times that people that use de-nitrators to control nitrates simply put in a small amount of sugar into the de-nitrator as food and the unit does it's thing. I have a Aquamedic de-nitrator unit which comes with Deni-balls which provide the food and it lasts around a year. Will the freshwater de-nitrator that I have work with saltwater? Is it just the same thing? <About the same yes... and same anaerobic processes involved, with sugars...> After I get my new tank, the only thing that I would have not replaced from my original freshwater setup would be the cabinet. Everything thing else has been replaced or changed. If I knew this was going to happen I would have brought a hole new marine setup and just kept the freshwater tank running with freshwater fish in it. It's really funny how things turn out! <Yes... indeed> While I am in the replacing mood, is there anything that I should have that you recommend, before the new tank arrives? <Nothing comes to mind... but do read over a couple hundred of these messages per day...> Many thanks for your help. I really appreciated it :) <You're welcome my friend. Bob Fenner> Warmest regards, Lucien

Broomtail wrasse/NatuReef's denitrator Bob; I regularly peruse the WetWebMedia website and go through old and newly posted FAQs. I find most interesting even the questions that don't necessarily apply to me or my systems.  <Yes... a useful mechanism of "making known" what needs, might well need be> I currently have a 45 gallon reef tank and a 180 gallon fish only both of which I'm thinking about increasing in size. My questions are twofold. You have no information on broomtail wrasses other than they are two big for aquarium use.  <Splendour, Cheilinus wrasses... can be very hardy aquarium specimens... as you/I state... for very large systems only> Since I have acquired I find that they are a splendid looking species with a easy going community personality. No subversive behavior with my other fish consisting of varying sizes between the smallest flame hawk and the largest emperor and queen angels. I realize that the fish will all grow and hence my plans to upgrade the size in the future. How quickly do the broomtails grow? I would imagine it would depend somewhat on the quantity of food that they eat? <Hmm, yes... a few inches per year, especially initially... something like this is my best guess for "average" size at the end of 1 year: 6-8", 2 years, 8-12", 3 years 9-15"...> Second question is the NatuReef Denitrators. I've been running one since I started a little over two years ago with the original 125 since upgraded to the 180 I currently have. Why no suggestions to people with fish only tanks to use these products to help improve water quality between changes? <Many pitfalls to avoid here... in dealing with such units and describing their practical use on the Net... as I'm sure you do appreciate... most Denitrators are wildly inconsistent in their performance... requiring almost constant checking and feeding (most with sugars, some with alcohols... other stocks), adjusting flow rates... The best "ones" are those that are used redundantly... with people not fooling with them (good luck)... Hence my alacrity in promoting any but the "more passive" live rock, deep sand beds, real plenums sorts of approaches... > Fish are happy and healthy. Keep sg @ 1.018 and temp around 82 and they appear to flourish. All fish beside broomtail and emperor have been with me for 1 1/2yrs emperor (6-7") has been for 1/2 yr. Thanks for your input. <Thank you for yours. Bob Fenner>

Toadstool help and Aqua Medic Hi Bob, Once again I am emailing you for some more help! My fish tank is the one at http://www.cia.com.au/winone <Nice pix, layout... Anthiines sold to you as "starter fish"? Yikes> I have since added a lot more rock to the fish tank but I have not updated my pictures yet. The reason I am emailing you is because I have no idea when it comes to corals. I brought some corals that inflate (e.g. bubble corals) and they are doing great :) <Yes, Plerogyra are great beginner corals> I purchased two toadstools and shortly after I put them into the fish tank they shed their skin and every few days to a week they shed their skin again.  <This is normal> I use a turkey baster (it's like a big eye dropper) to gently blow water on the toad stool so that the loose skin comes off. This makes a mess in the fish tank as there is dead skin and what looks like white powder everywhere. This settles and disappears in about 30 min.s. Today, to my horror, one of the heads on one of the toad stools fell off. I picked up both stalk and head and disposed of them. The other toadstool looks fine. It is a different looking toadstool to the one having problems. The one that had problems had a short stalk and the one doing fine has a long stalk. The heads are about the same size. <Shape more dependent on physical conditions (circulation, lighting) and nutrition than species...> Can the dead skin coming off the toadstool pollute the fish tank?  <Yes, if too much in too small a volume of water, or if quality is otherwise compromised... These soft corals can produce considerable terpenoid pollution... engage in real chemical battles with other stinging-celled life forms...> Why is there dead skin coming off these corals? What can I do to keep these corals happy? <This is a "cleaning mechanism"... not to worry> What corals are good for a beginner? <Please see the beginnings of coverage of the soft and hard/true corals posted on our site: www.WetWebMedia.com and the associated FAQs files, and in particular the references listed there> Many thanks for your help :) Warmest regards Lucien Cinc PS: I had to remove the de-nitrator because it started to smell bad. <Yikes, good idea. Am not a big fan of these units due to these unpredictable qualities...> I tried my best to get hold of the orb computer to control the de-nitrator, but even AquaMedic themselves in Europe ignored all my attempts to contact them. I was NOT very pleased with Aquamedic at all :( <Really? Am very surprised... this is a great company (saw their German representatives at Aquarama in Singapore a couple of weeks back... Would you mind if I forwarded this message to their U.S. division?> PPS: I have also removed the UV light as I believe it is doing nothing. I was wondering, if the corals are filter feeders, would a UV light kill the food that the corals need to eat? <To some extent yes... if your system is otherwise "going well" and firmly established I would eschew the use of U.V. as well. Bob Fenner>

Re: toadstool (and Aqua Medic) help Sure. If there is a chance that I can purchase the orb computer + probe + solenoid + black tubing + Deni-balls I would be willing to give the de-nitrator another try. I am not sure if the orb computer requires main power? <Hmm, me neither... have you checked their website? It's on the WWM sites links page> In the US it's 110v but in Australia it's 240v. If it's just a simple A/C adaptor down to 9v or something similar then I would be happy to purchase all the above from the US. <Not a big deal as you know> I even called the Australia distributor with no luck at all. They did not even want to talk to me, instead they wanted me to ask my LFS to call them. Every LFS I have asked tell me it's an impossible bit (i.e. the orb computer) to get. I was told there is going to be a 4 month wait just to get Deni-balls! What was I supposed to do in the mean time? <Contact the manufacturer... I am going to ask their US rep. to respond to you> How is AquaMedic supposed to sell things in Australia when they can not get any stock over here? <Got me...> Thanks for all the info on toadstools. I'm pleased the skin shedding is normal. When the head fell off the other toadstool I was very distressed. I will check on WWM web site for more beginner corals and stick to them for the moment :) <Ah, good> A very warm thank you for all your help, my friend :) <You're certainly welcome. Bob Fenner> Warmest regards Lucien Cinc

Re: Aqua Medic assistance Dear Bob, thank you for sending me a copy of this mail and giving me a chance to take care for Lucien. I have pushed our Australian Distributor to help him. <Outstanding! Will post your timely, positive response after his on our site: www.WetWebMedia.com. My appraisal of your products, Aqua Medic, AB Aqua Line stands. Excellence. Bob Fenner> best regards Manfred

Re: AB Aqua Medic U.S. Dear Mr. Cinc, I received an e-mail from a friend of yours Mr. Fenner. I understand that you are having trouble finding equipment to work with the nitrate reducer. The egg smell that you referred to is hydrogen sulfide this is caused by over feeding the unit and the Redox potential is to low to correct this reduce the feeding rate and increase the flow rate of the unit. As to where you can purchase the Redox controller and probe. There are 2 types of probes that we carry for the Redox controller one is for a low pressure system this unit has 2 clips that hold the top on and then one for a pressurized system this unit has 8 clamps holding the top on. Where to purchase the Aqua Medic line of products customaquatic.com this is a company I have been dealing with for some time and has a good reputation. You can call 1-800-397-7238 and ask for Todd and he can answer most of your questions as well as give you prices. If you have any other technical questions about our products please contact me directly by phone at 1-866-419-0086 or e-mail at AquaMedic@ev1.net or jutley@ev1.net. Thank you John Utley AB Aqua Medic Customer Service AquaMedic@ev1.net Toll-free 866-419-0086 Phone 281-419-0086 Fax 281-419-0502 <Again, outstanding. And do want to second the referral to Todd (Gabriel) of Custom Aquatic. I know him to be professional/very customer service oriented. Bob Fenner>

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