FAQs about Deep Sand Beds 6 Related Articles: Deep Sand Beds, Marine System Substrates (Gravels, Sands) by Bob Fenner, Marine Substrate Options by Sara Mavinkurve, Live Sand, Biological Filtration, Biominerals in Seawater, Understanding Calcium & Alkalinity, Nitrates in Marine Aquariums,  Related FAQs: DSBs 1, DSBs 2, DSBs 3, DSBs 4, DSBs 5, DSBs 7,  & FAQs on: Rationale/Use, Dangers, Physical Make-Up, Biological Make-Up, Size, Location, Depth, Conversion to/from, Maintenance/ Replacing/Adding To, & Live Sand FAQs, FAQs 2, Live Sand 3, Identification, Selection/DIY, Systems/Placement, Biota, Maintenance, & Marine Substrates, Live Sand, Mud Filtration 1, Plenums, Nitrates in Marine Aquariums, Refugium Substrates/DSBs, Many animals will dig up a sand/gravel bed.

Will any sand be ok for substrate? 08/04/2008 Hello WWM thanks for all your help thus far. <<Hello, Andrew today>> I have a 6' tank that was fish only that has now been changed over to more of a reef setup with loads of xenia that has increased about twenty fold in the last five months and a few other corals, colt, toadstool, hammerhead, and a Condylactis. I wish to replace the substrate from crushed coral to a very fine sand. Reasons being aesthetics (I want the substrate to be perfect looking) and to lower nitrates. I've read on your site that I should do this bit by bit and not plunk it over the existing substrate. That I should work from one end across to the other removing existing substrate as I go. My questions are: 1) How much should I remove at a time? 10" in width or can I get away with more <<I would do a 1/4 at a time, leave a couple of weeks in between swap outs to enable life to transfer to the new sand>> 2) Present depth is about 1.5". Is 2" of the fine sugar sized sand ok <<Yes, absolutely fine. Just bear in mind that if you want sand burrowing fish in the future, more like 4 inches or more would be more suited>> 3) Can I use "any sand". the local supermarket sell a perfect looking fine sand for child use, it says it has been cleaned but that's it. I don't know what type of sand it is or what it has been cleaned with. as its for child use I would assume no bleaches or toxins in in but I am trying to contact the manufacturer. Does this matter? <<Personally, I am just a stickler for sand choices and would only purchase / recommend a proper marine substrate, like CaribSea sugar grade reef sand>> 4) If its ok should I also buy some live sand and apply top? any benefits, like speeding up the amount of sand changed at a time? <<Don't see any real need as life will transfer from the old sand. If anything, just save a few cup fulls of the old top thin layer of sandbed, and spread over the new sand to promote life>> 5) Will fine sand affect my PH or any other parameters in the tank - buffering ability etc. I am mainly concerned about my xenia. <<Nope, all shall be fine>> 6) I have heard that the only negative with sand of this size is the cleaning. I've never really cleaned my substrate (didn't know I had to at first) and as a result algae has formed at the bottom. will vacuuming be a problem or will my critters suffice, sand sifting stars and snails 0.5" hermit crabs? <<Normal sand sifting snails, hermits, bottom grazers etc will suffice>> Thanks for all you help, Lex <<Thanks for the questions, hope this helps. A Nixon>>

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. DSB Questions - 08/26/05 I have been reading quite a lot of your information on DSBs. Because of your information I have decided to go with a DSB for filtration on my 90g reef tank. <<Super!  I'm a DSB fan myself.>> My proposed setup is a 30g with 3 separate compartments. The first is the stable water level where the skimmer goes 10"X12", the second is the refugium area, 21"X12"X14"deep, and the last area is for the over flow with mechanical filter and a small portion of bioballs then to the return pump.  My plan is to illuminate the refugium area counter to the main tank 14 hours a day with 40 watts of PC lighting. <<Sounds good>> The 4" DSB will be filled with macroalgae and detritivores.  Flow rate is directly proportional to the return of the tank, I have a 1300 gph pump on the return.  Do you have any suggestions or modifications to this set up? <<It looks like you have things well in hand.>> In your FAQ's I have read that DSBs should be installed properly and proper maintenance.  What is the proper installation and the proper maintenance that you are referring to? <<Well Dallas, proper installation would be to use the correct grain size at the correct depth.  My preference is sugar-fine aragonite at a minimum depth of 4 inches (six is better).  The larger the grain-size, the deeper the bed.  Maintenance refers to high water flow...high water flow keeps detritus in suspension and out of the sand bed.>> Thanks for all of your help. Dallas <<Always a pleasure, EricR>> Optimum Deep Sand Bed box dimensions? Hail crew! <Greg> Thanks for helping with my other question. I won't waste time by repeating it here, but the tank is much happier since I followed your advice. I've read the deep sand bed articles and want to get the benefits of one--nitrate removal is my main goal. However, I don't have a lip on my stand and think the deep beds look ugly. My solution is to build what I'm calling a sandbox. My tank is 100 gallons (5 feet long), and I'm leaning toward a DIY acrylic box (no top of course) of 5" deep x 4" x 20" with a 4" deep sand bed.  It won't get me all the benefits of covering the entire bottom of tank, but I'm thinking it has to help somewhat. And, I can hide it in the back behind some rock. <Sounds like a good plan> My question is--assuming that the volume of sand will remain approximately the same, would I be better off maximizing the length and width (and keeping it at 4" deep) or going deeper (6" deep or even more) and having a smaller length and width box? <Mmm, deeper is generally better, but minimally so here> Aesthetics is part of what I like about the hobby, which is why I'm limiting the size and not going with both very deep sand and large length and width. I have to choose! <I do understand, and agree> Here's  the same question in streamlined form. If the dimensions matter, which of the following would you choose if goal was nitrate removal? (all have appx same volume in sand) 4" deep x 4" x 20" 6" deep x 4" x 14" 8" deep by 4" x 10" <The first> Thank you for your time! <Thank you for writing. Bob Fenner>

DSB for NNR...(nitrate control and refugia) 6/22/05 Hello, I have set up 75 gallon refugium for NNR (natural nitrate reduction).  I can only get the 1-2mm aragonite here in South Africa.   <Heeeey! Are you aware of the SA forum? Good local networking for you (seeing tanks, frag swaps, etc): http://sareefkeeping.com/forum/index.php> What is the perfect depth for the bed, 6 inches, 7 inches?   <4-6" minimum indeed. But with strong water flow above it when using more coarse sand. I'd opt for at least 6", mate.> Also, what else do you recommend I put in the refugium?  Live rock, Caulerpa?   <Neither. LR impedes flow and has less benefits there... Caulerpa is noxious if not toxic and too tedious to keep long term (risk of vegetative fission, etc.). I'd recommend a Chaetomorpha or Gracilaria colony for safer algae and as good or better pod/plankton production> Would it benefit my system to add some coral to the refugium as my main tank is FOWLR? <No, my friend. On the contrary! The coral will prey on zooplankton that the refugium generates for your fishes. Please consider reading our extensive refugium coverage in "Reef Invertebrates" where a full chapter is dedicated to styles, benefits, disadvantages, etc> Many Thanks, James. <kindly, Anthony>

- DSB, Sand Selection, and DIY LR Questions - Hello, WWM Member! It's so nice to have such a great resource to help those of us without a lot of hobby experience.  I'm still in the planning stages for a 70-90g peaceful reef tank, and I'm confused on certain points.  I have done TONS of reading on WWM regarding these questions, and I haven't found consistent answers... perhaps some of my questions have no conclusive answers! First, regarding DSBs.  I know that optimally, 6"+ is best.  Is 6" optimal? <Six inches is the minimum, not optimal. Eight to ten inches would probably be optimal, if not always practical.> If not, what's the optimal depth?  (I know that making it too deep can cause hydrogen sulfide problems; at what depth do problems develop?) <Not sure this is empirical. I have a 12" DSB sump that's been running for a year and have had no problems with hydrogen sulphide. Think sulphide problem may result from sub-optimal depths, where the proper bacteria that would make use of this stuff do not exist.> I've done a lot of reading regarding substrates, and I'm confused.  I've read that Jawfish and other burrowers are best kept in fine sand with some coarse material to aid their burrowing, and that these fish move around the bigger pieces to their liking; I've also read that coarser material mixed in won't harm anyone.  However, I've also frequently read that you shouldn't mix substrate sizes so channeling/packing is minimized. <I mix substrate sizes all the time - especially in the fish tank - seems to allow for better fauna development in the substrate.> So, the question: if I'm keeping Jawfishes, gobies, and the like, what should I do?  Should I stick with pure sugar-fine aragonite sand, or add some crushed coral, or add even coarser material like crushed shell? <I'd do all three.> If I should have coarse material, what ratio is best? <Perhaps 1/3 of each.> I just want to make sure they have the best substrate possible. Also, I'd like to make some GARF Aragocrete "Reef Tables" and a couple caves for my tank (I'll have plenty of "real" live rock, of course).  I've heard some people have no problems, and others make claims that the cement adversely affects tank chemistry.  What's the truth? <The truth is that anything cementacious would need to be cured for a while - months - in a weak acid solution (vinegar would do) to help bring down the highly alkaline nature of cement products.> Would I be foolish to use Aragocrete, or will I be fine? <No... this has been done for decades in public aquariums and the like - is perfectly viable as long as you take the appropriate precautions.> Oh, one last thing, if I may.  I plan on principally keeping quiet fishes, like gobies, Banggai Cardinals, blennies, and perhaps a Jawfish or eventually a mandarin (with a refugium, of course).  But... I (and my wife) would love to have a yellow tang (Zebrasoma flavescens).  Would it be too boisterous or aggressive a feeder to mix in this type of tank? <Would be fine.> I'm worried that the other fish wouldn't get enough food... Also, is there any species of clownfish that could coexist peacefully, as well, or are they too aggressive? <My favorite are the true and false percula clowns - they seems to be the most docile of all the clowns and seem to get along with just about anyone that won't eat them.> Thanks so much for your time and help; I truly appreciate your advice. Scott <Cheers, J -- >

Using a DSB and LR Hello! <Hi there> I have not purchased my tank yet as I have been researching the different filtration setups. Since my budget is very small, when I came across the DSB method I thought it would be more economical in the long run (since there is a cost to replace filter media and electricity costs.) However, the more I have read into it I began to realize that as with all things in saltwater aquaria...there is not one way to do it. <Ah, yes...> I did my research, but i still have questions. I am thinking that I should do a deep sand bed (mine will be 5 inches to accommodate a jawfish which I intend to purchase at a later time) without a plenum on the bare glass of the 29 gallon  tank. I have used a sand bed calculator and found that I will need 73 pounds of sand. Some aquarists recommend using 50% live sand. 25% crushed coral, and 25% crushed shells. Another aquarist said in the Aquarium Fish magazine that the coral and shells would be too large and coarse for the delicate organisms (such as worms) <Mmm, no> to move in the substrate without injury. I also think that the coarser substrate would damage my future jawfish. <Again, not... Opistognathids dig about, move the larger bits where they want... in captivity, the wild> This same aquarist suggested using 10% of my tanks total volume in pounds should be live sand. This completely confuses me--how can the volume (gallons) turn into the mass of the sand (pounds)? <Just a rule of thumb likely> I would appreciate it greatly if you could tell me how much live sand to put in my future tank, and if not all 73 pounds, what other substrate I can use to fill up the level to 5 inches. <I would just buy/use five, perhaps ten pounds of actual LS... the rest will be inoculated sufficiently hence> Please keep in mind that my budget is very small. Speaking of my small budget, I am interested in purchasing live rock to aid in filtration, to beautify my tank and so I can later have coral and anemones. I have read that I need one pound per gallon of live rock. In my area that runs about 200 dollars. (for the 29 gallon tank) I am hoping that I either do not need that much because of the DSB or that I can add it ten pounds at a time. <Don't need that much, can add a bit at a time... best of course to re-cure outside the system> I am also thinking I will definitely need a protein skimmer, but perhaps with this filtration system I don't? <A useful tool... you can try it without... more expense in the long haul in synthetic water... to maintain quality> Also when I place LR in the tank wouldn't I need to put it right on the glass bottom so it doesn't fall and crush my fish? <Mmm, no... not really... Place the larger pieces first, securely mount smaller on top... as the DSB dissolves, gets tunneled about all should settle a bit w/o falling> So then would I put the live sand in afterward around the live rock? Or is it okay for the LR to be on top of 5 inches of sand? <The latter> I know these are a lot of questions, but with all my research I have not found a better place to get a straight forward answer. Thank you very much for your help and time! Jennifer <Glad to share... keep investigating, sorting through your possibilities, choices. You'll do fine. Bob Fenner> DSB Critters (Too Disturbing?) - 06/12/05 Hi crew, I am replacing my 40gallon long aquarium because it leaks and is scratched up with a 55 gallon when I can afford it, and I have been thinking about filtration possibilities. <<Always good to think ahead.>> I want to use my diy pvc skimmer that I had to disassemble because it was leaking horribly (it seems to work very well when I was using it for my 40gallon...). <<Mmm...perhaps time/chance for some reengineering.>> Anyhow, I was wondering about the idea of having a 5-6" DSB in the 55g, but some of the "talk" at reefcentral.com about DSBs...well I don't know if it will "crash" or not if maintained properly. <<With a proper substrate (sugar-fine sand) and adequate/proper water flow this is of little concern.  I've had DSBs that were 7-8 years old with no issues (Anthony has one in the 10 yr. range).>> What I was wondering is are sea cucumbers (the sand mopping variety) bad for a DSB? <<Love'em myself...have two in my system with a 6" DSB.>> And, are hermit crabs also bad for DSBs? <<Don't know that they affect a DSB one way or the other.  But I prefer to keep them out of my tank for their opportunistic dietary habits.>> Another question is will a yellowhead jawfish disturb a DSB too much, possibly causing it to not function properly? <<Is a possibility, yes.  But will likely find a spot to its liking and stay...becoming a small concern to the DSB overall.>> Thanks, Adam <<Regards, Eric R.>> - DSB Grain Size - Hi Guys, I have a quick question about substrate selection for a DSB.   I plan on putting 5+ inches into a 125G aquarium.  I see that there are two sugar fine substrates from CaribSea .  Their standard oolitic sand has grain sizes of 0.2 to 1.22mm.  They also have a more expensive oolitic "select" with grain sizes of 0.5 to 1.02mm.  Is there a difference in performance that justifies the difference in price? <I'm not aware of one, but would think the higher price is just due to extra processing.> I don't want to spend more than I have to, but I don't want to cause myself grief over a few bucks either. <Think you'll do just fine with the standard oolitic sand.> Thanks for your help and keep up the good work. Larry <Cheers, J -- >

Deep Sand Beds...Silica Sand? - 06/03/05 Hi, Home Depot has 30 mesh, which is fine grade material. It is made for sand blasting. The bag says silicone. Are these pellets safe and do-able for a deep sand bed? <<Silica sand is very "do-able" for a deep sand bed.  Just be aware you won't get any buffering capacity as with aragonite, nor is it as soft/easy on the skin of burrowing creatures.>> Thanks, Dan. <<Welcome, Eric R.>>

Deep Sand Beds? #2 - 06/03/05 Hi, I understand that the stuff I can buy at Home Depot is silica sand.  For a 100 gallon tall, how deep does it need to be to be effective? <<Same as if it were a 20 tall...4" minimum, though I recommend 6".>> Thanks, Dan. <<Welcome, Eric R.>>

DSB Sand Storm From Flow? - 06/03/05 Hi,  I've been reading through lots of the FAQs on your site, but haven't found my answer. <<Ok>> I'm planning on setting up my first reef aquarium with a sugar fine DSB of about 4-5inches in a 125gal tank. <<Great!  Use DSBs in my systems too.>> I also plan on running a Mag 7 for my sump and a Iwaki MD20RLXT on a closed loop for circulation. <<Not enough flow in my opinion...do consider increasing...maybe double?.>> My concern is, will the circulation pump with a PVC manifold create too much flow that it will stir up the DSB and shoot sand all over the place?  How do I avoid it? <<If the outlets point directly at the sand bed, yes.  Expect some movement of the sand, but you can play with/adjust the flow to keep much of the bed in place.  One trick is to add a very shallow layer of larger gravel in high turbulence areas.  The bed will also stabilize some as it ages/binds with bacteria.  I have 11,000 gph of flow in a 375g tank with a 6" sand bed...so I know it can be done <G>.>> Thanks. <<Welcome, Eric R.>>

Deep Sand Bed (Max Depth?) - 05/16/05 One article reads:  "The depth of the bed (and particle size) are critical to provide the correct conditions. If the sand bed is not deep enough, and the oxygen level does not drop enough, the sand bed will produce nitrite from the nitrate. A disaster. Conversely, if the sand bed is too deep, the entire bottom of the bed can turn anoxic and produce sulfur dioxide. If this happens the affected sand turns black. If this black area is disturbed or sampled it releases the characteristic rotten egg smell. This chemical is of course toxic"  What is too deep? what is the max a DSB can be? <Is this from the WWM Website? <<Is assuredly not. RMF>> Do have a read here and at the related links in blue at the top of the page - http://www.wetwebmedia.com/deepsandbeds.htm  Regards, Eric R.>

DSB 100 gallon tank containing 300 lbs live rock, coral, 1 blue tang and 2 maroon clowns, and decent clean up crew. Display tank has live sand. (bought from store) Tank is filtered with a 30 gallon sump underneath (low profile Rubbermaid container with 32 gallon Rubbermaid (designed for garbage) within sump filled with 19 inches of Southdown sand. Yes, 19.....had access to it and plan to one day upgrade to a 1,000 gallon tank and use this same filter. Also have a protein skimmer rated at 240 gallons made by Coralife. Sooo, obviously, this down south refugium sand has no life in it. should I leave it alone and expect it to denitrify? Or must I seed it and if so, with what? Won't seeds or live particles from the live rock/live sand in main tank enter the refugium eventually and seed it by itself? I never disturb the refugium. Is this ok or will lead to the production of hydrogen sulfide? Thanks for your wisdom.  <Read here my friend. http://www.wetwebmedia.com/deepsandbeds.htm James (Salty Dog)> 

Transferring my DSB Hey Crew. Will here from Ireland. I searched your FAQ's with no joy, so here goes. I want to transfer my DSB of oolitic aragonite that is 7" deep in my sump to my new inline refugium that has twice the volume. I was wondering should I remove the first half inch of my existing bed to inoculate my new bed and discard the rest or is there a better way? Cheers Will <Mmmm, I wouldn't toss any of it... but it might be a good idea to quickly scoop out the top half as you state, and quickly remove the lower half (scoop or siphon), rinse, place it in the new tank, then place the original upper half on top of this. Bob Fenner> DSB & BBT - 05/06/05 Hi Helpful Guru(s), <Greetings> With your help, I have claimed some success with my fish keeping for the past year & you people are the "gold" in our hobby. Thanks!! <Thanks for the kind words.> There has been a debate among my reefer friends on DSB (deep sand bed) vs. BBT (bare bottom tank). The DSB has been blamed as nutrient sink & BBT is the new & better way of doing it, if you are into SPS. With better skimmer technology, there are claims that one should do away with the DSB & just do BBT. <If the DSB is working for you, why would you do this? Doesn't it make more sense to enjoy/reap the benefits of both?> With BBT, you can blow the power heads any way you like & not be afraid of creating a sand storm etc... <Won't argue that...> What is your view on this issue? <I like/prefer the DSB myself. Both can/do work, But it comes down to proper husbandry and proper application of the chosen methodology. I'll grant you that a DSB may become problematic, but ANY methodology will end in disappointment if you don't bother to research and apply it properly.> I understand that DSB helps mainly in Nitrate Reduction. Right? <A primary consideration, yes, but other benefits to be had as well.> Even with a powerful skimmer only without DSB, can one get zero nitrate? <One can get zero nitrate without a skimmer OR a DSB. It becomes a matter of adjusting stocking levels, feeding, water changes, manual detritus removal, etc.> Or, the reason that BBT works in SPS tank since minimum feeding is required & hence minimum NO3 generated? <Faulty logic/information my friend. Feeding and water flow rate above lighting in my opinion (and others here) for success with SPS and indeed all type reef tanks. The idea is to find and correctly apply a methodology where you DON'T have to starve your tank.> I have a DSB tank housing SPS. Thinking of upgrading to bigger tank. How do I move the existing sand in DSB to the new tank so that all my bio filtration is intact & I need not go through the cycle of new tank? <So, you want your cake and eat it too eh? <G>.  You must understand, the sand bed is made up of layers of micro- and macro-organisms. The organisms develop and function, indeed survive at differing depths within the sand bed. It's not reasonable in my opinion to expect to move a sand bed without experiencing some mortality of these organisms.> If I move the sand just like that, I am disturbing it & may experience nutrient leach & toxic tank, right? <You may, yes, maybe.... But your biggest hazard is a brief infusion of nutrients to feed nuisance algae, the so called "toxic tank" is more myth than reality. In my experience, any "toxic gas pockets" that are released exit the water column very rapidly, facilitated by good/proper water flow, with virtually no effect on the tank inhabitants.> Does it look like my only viable way is to cycle a new tank with new DSB until it is completely cycled (i.e. 2-3 months minimum); then I can move my live rocks & my SPS over to the new tank? <Not at all. You will have mortalities within the sand bed as stated previously, but not everything will die, thus providing a "kick start" to the cycle process. You will need to monitor water parameters to be sure, but I believe it's reasonable to expect the relocated sand bed to cycle within a couple weeks or less. You might even reduce that time by using a portion of the sand to infuse life in to a new sand bed if you like. Consider the fact that you will be also adding cured/mature live rock to the system.> Gee, now you can understand why I am tempted to go bare bottom tank, no such problem in future; just move live rocks & live stocks. May I have your honest view on this matter. I would appreciate it. <Have tried to do so. Relocating a sand bed is an arduous task. I would recommend seeding a new sand bed with a sizeable portion of the old bed, move your rock and livestock, along with most of the "old" water to the new tank, and go back to enjoying the hobby my friend.> Thanks in advance. <Regards, Eric R.>

DEEP Sand Bed- Deep Problems? I have a 100 gallon reef setup with about 300+ lbs of live rock, 2 Maroon Clowns (paired) 1 Blue Tang, 2 Blue-lined Gobies and 1 Orange Shouldered Tang. They are all about 2 to 3 inches in size. sand in Tank is about 4 years old and has been filtered by a wet dry and a Euroreef rated at about 200gal. Everything has been fine and stable except for nitrates which have stayed at about 10 to 20ppm. For 4 years, I have been doing 10%weekly water changes until I decided to get rid of the wet/dry and go with a DSB setup. So about 2 months ago I bought a 32 gallon Rubbermaid tall (used for garbage) and put it in a another Rubbermaid low container and filled the 32gallon with sugar fine Southdown sand almost to the top, creating a DSB of 19 inches. Basically, I have a refugium containing 19 inches of Southdown. <WOW!! That is a REALLY deep sand bed! You really have to believe in the value of DSBs with that kind of depth!> Do I need to add stirrers or will the live rock provide them? <Well, I would add some stirring creatures if that is your goal.> I also added Southdown into the main tank(3 inches now) and 2 months later can see little air bubbles forming in the sand. (Nitrate being reduced? sulfur?) <Nothing to worry about...That's evidence of denitrification occurring.> I am also starting to get some Cyano growth, despite the numerous power heads I have in the tank and sufficient circulation. <There are a number of factors which contribute to Cyanobacteria growth; insufficient flow is only one of the possibilities. Read up on Cyanobacteria here on the WWM FAQs.> Did not add any stirrers and only siphon the top of the sand during water changes. Should I disturb/stir the sand or not? Some say not to touch the DSB. Others say it must be stirred. <I would not disturb anything but the very top 1/2" or so of the sand.> This is confusing. I feed 1 once daily very little enough for a 1 to 2 minute feeding. What can be causing the Cyano? I didn't have this problem before the DSB. Thanks for any help. Rico <Well, Rico- deep sand beds are efficient at denitrification, but they are not a guarantee of trouble-free systems. Nutrients can still accumulate, which can contribute to problems. Before you draw any quick conclusions about the merits or problems of the DSB, see how it works in your system. Continue good husbandry and overall water quality management, and I'm sure that the Cyanobacteria will vanish in due time. Hang in there! Regards, Scott F.>

DSB With FOWLR (doesn't have to be in the display tank) - 05/02/05 Hi Eric, < Hi James! > Thank you for your excellent answers. I think you've hit the nail on the head. < Be sure and tell my boss <BG>. > The substrate will be the nitrate source. It is the 1-2 mm aragonite and about 3-4 inches deep. One size up from sugar fine. < Can be a recipe for disaster...yes sir. > I will reduce it down to 1 inch. < Excellent! > If I leave one corner deeper, will the queen Coris wrasse be happy enough. Looking at him he is probably around 6-7 inches. He does need deep sand for his bed time, as you know. < Yes he (she?) does, can I assume we are talking about Coris formosa? Yes, do place some rock in a corner to create a built-up area of sand for the wrasse. > I will then buy sugar fine aragonite for the refugium. What is ideal in your opinion, 6 inches, 7 inches?? < Minimum of 6" - 8". > Also, if I can't get sugar fine aragonite, will sugar fine coral sand work? I don't think it is aragonite. < Either one mate, you could even use silica sand. You just won't get the buffering capacity of a carbonaceous compound. > Finally, if I start to replace the bioballs with more live rock in the main tank, how many lbs of live rock per what amount of bioballs do I need? I think I have around 1000 bioballs. < Don't worry about how many "pounds" of rock, just add as many fist-sized pieces that will fill the space. > Oh, one last thing. I had a fish die of white spot in my quarantine tank. It kept on re-infesting him, copper just didn't work. I must have went wrong somewhere. Anyway, I used the pipe for my siphon. Is boiling it enough to kill off any unwanted parasites? < Would think so... > Many Many Thanks, James. < Most welcome James. Regards, Eric R. >

DSB Hello Mr. Fenner (or fellow aquarists) <James today> Thanks for your webpage. <You're welcome>  It's an awesome resource. I've got a quick question: I'm currently cycling a 210 gallon tank and I want to go with a deep sand bed. I've read that 4-6 inches is desired. Is it possible to have too much sand? Currently my tank is pretty even between 5 and 6 inches but several fellow aquarists feel that this is too much sand.  <John, read here. http://www.wetwebmedia.com/deepsandbeds.htm James (Salty Dog)> Any help would be much appreciated. John Dixon 

Reef & DSB Maintenance  Hi! I guess I can't specify, but if I could, it would be to Mr. Fenner and Mr. Calfo. I am enjoying your new book Reef Invertebrates. I have been convicted about some things I'd like to change. <Interesting> A man at the LFS set me up and I trusted him but he was just a bit behind in his information. And now I know more and want to re-do a few things. Already have. I bought a skimmer, upgraded my lighting, installed fans in my hood and now I have a very stable temp all the time. You discuss deep sand beds. It makes sense and I'm having a tough time keeping clean the crushed coral. Plus every time I deeply siphon it I feel like I am sucking up some of the mandarin's food! I wish I didn't have to disturb it so like that! I am meticulous in my water changes. I thoroughly siphon the substrate, clean all filtration pads, pre-filters, etc. <Mmm, biological cleanliness is not sterility...> No trouble with the usual tests. Even nitrate is as low as it gets (Got the lowest when I removed all the Cell Pore's balls which were pretty yucky!) . No phosphorus, ammonia, nitrite, and this is after I followed your advice and took out the bio balls. I am waiting a while to take the bio wheel out just to be sure. I put in a refugium that has a nice deep sand bed with Gracilaria, Ulva, and Chaeto and tons of copepods and amphipods. Now I wish I could do it for my main tank. It is a 90 gallon with a Tidepool sump, with skimmer, UV, adequate pump, two powerheads, adequate lighting. The fish are Red Sea purple tang, blue hepatus tang, flame hawk, ruby-headed fairy wrasse, sailfin blenny, royal Gramma, 2 ocellaris clowns, mandarin, and a coral beauty. This is the last of the fish to be added with a desire to keep some easy corals. Do you think I am one of those overstocked? <You're right about there> And now for the questions about the sand/ crushed coral change. In the book you say pick one size of grain and stick with just that and try to get spherical. Did I understand this right? <Yes, this is ideal> So say I removed portions from week to week replacing with this sand. Yes I know it needs to be between 4-6 inches deep. Will all the junk stirred up removing the crushed coral and putting in that sand bother anyone? <Perhaps> Will the fish be really compromised? <Maybe> I do have a patch of green starburst polyps. That is the only coral. What method could you suggest for easy removal and minimal junk stirred up of the crushed coral? <A large diameter siphon to suck it up/out... a good sized container/s to allow the water to settle, decant back to the tank... and/or a bunch of water pre-mixed, matched for replacement> What is your suggested method for getting that live sand in there without a massive cloud? Or you may simply think I should leave it alone. I just wish I could do a simple water change without the incredible time put in to siphoning so long every week and just sit in front of the tank instead of always being IN the tank! And to find live sand... no one seems to sell the real live stuff in large quantities. It seems I just buy lots of some that supposedly has lots of bacteria in it. Then I am supposed to inoculate it with a small purchase of say, IPSF s Surfzone Live sand activator (what if that is a different size sand, though?). <No biggee> However, I did buy that once and stuck it in with my crushed coral and everybody in the tank thought it was great feeding and ate everything up. So are folks like me destined to be stuck with bad decisions made in the beginning or is there hope of a healthy, positive transition?  <Mmm, you seem to be (along with myself, a few known others) in the small minority of folks that will read, learn "second" or other hand w/o having to personally experience less-favorable experiences first-hand...> Pardon all the detailed questions but I really want to do this right this time. Again, thank you for the book and when is the next one coming about the corals? I don?t want to start purchasing them until I do some reading. Thank you again and I look forward to what you will share with me. Sincerely, Renee' <Do investigate, perhaps join a marine club, attend some of the "group of groups" club meetings likely IMAC, MACNA, the various marine conferences... for input, inspiration... You'll do fine, take your time... Bob Fenner> 

Upon What Bed do Sleeping Dogs Lie? Not a Deep Sand Bed! Hi Guys <<Marina-guy this morning hey.>> Many thanks for the continuing support, on this great site. My question is related to deep sand Beds. <<Ok.>> I have been having problems getting my Nitrate down and I am setting up a refugium with a small 12x12x10 tank next to my main sump, this will be fed via a water supply from my old counter current skimmer. (have upgraded to a Turboflotor 1000) The water will come in to the tank then be skimmed and returned via the skimmer to the mains sump. Where the main pump will return it to the main tank. My idea is to have around six inches of sand in this refugium to help as a de-nitrifiers. <<Ok. With that much sand you'll not have much room for macroalgae, those are helpful as well.>> What I am having problems getting my head around is what size of sand to use, I have spent a few hours sifting around 50kg of coral sand to give me 2 different types of sand. <<NUH UH! Seriously? You've been sifting through the sand? That sounds like something I would do! <giggle> >> Type 1 is very very fine, the sort you could easily make a sandcastle from, and looks like it compacts very easily. Type 2 is much more coarse and the grains are around 1-2mm, much more loose than Type 1. Which one would you suggest is the best to use? <<Either one, really. I've seen DSBs that looked more like Mud Beds, and others that looked like really deep gravel. The larger size, Type II, will not present the same problems such as cloudiness, remaining in suspension upon disturbance, etc. Also, if it's crushed coral, we don't have to worry about sharp edges harming any detritivores you may wish to place in there. I don't know how large the main system is, but a box that's under 1'cu seems a little small for larger setups (55g and over). In any event, you really can use either one, or both. Generally, the larger the particle size, the deeper the bed will need to be.  Start here: http://www.wetwebmedia.com/deepsandbeds.htm and note the top photo shows a tank with a substrate that is clearly not just sand. Both types CAN and do work, my friend.>> Best regards Robbie <<You're welcome. Marina>> 

Upon What (sand) Bed do Sleeping Dogs Lie? Part Deux and the Idiosyncratic Englishman Hi Marina <<Hello again Robbie.>> Firstly my apologies for assuming my reply would be from one of the men folk on WWM, and not one of its fair maidens <<Hee.. we fair wenches thank you!>> Many thanks for the speedy reply. <<You're very welcome. This was an easy one for me.>> So I did not really need to sift the sand... <<Nope.>> ...us Brits have some strange pastimes eh? <<Yeah, and I hear you lot drink this thing called a "Shandy". You're not one of those shandy-drinkers, are you?>> The main tank is 100 gall but has a 1.5 inch bed of crushed coral with around 90kg live rock, Have a suspicion that this is acting as a nutrient trap which is causing the prob.s with the Nitrates. <<The live rock is really quite helpful in this regard, ASSUMING it is of good quality. Know that good live rock actually contains some anaerobic bacteria that further break down nitrate into nitrogen, et al. Also, the crushed coral does require a good deal of maintenance, debris/detritus accumulations are problematic. A sand bed in the display may be an option, since those 90 gallon tanks are rather tall.>> I really just want the 'fuge just to help with Nitrates, if I go with the really fine sand then I could add a sand sifter star to this to keep it stirred? <<Yes, and you don't have to have sand to help with nitrate reduction, though creating an anaerobic area is the idea here. Also, uptake of nitrogenous wastes/nutrients by Macroalgae helps prevent its buildup in the first place. The refugium is an excellent idea/move, but can be further expanded upon.>> Thanks again for all the help. Robbie <<You're quite welcome, and do read that link I sent you, along with the others. Also, find yourself reefs.org, Advanced Aquarist online magazine, as well as Conscientious Aquarist online magazine on our site. Should be more helpful information there. Marina>>

DSB info for coral propagation 3/16/05 Hello, I have enjoyed reading many of your informative articles in the past and hope that perhaps you can help shine a light on a number of questions that I have. <glad to do so :)> I am attempting to start a greenhouse grown coral farm. I have a number of personal tanks in which I have used DSBs to assist in environmental filtration. Presently I am setting up a 800 gal system and am investigating other sources for sand to use in these systems. I can purchase aquatic sand from my sources but have been reading a lot of literature that says if you are not buying "live" sand, you are over paying for basically playground sand. <not true... there is no need for so-called "live sand". Its not needed, and frankly... many of the products sold as "live sand" are really a joke. Carbonate sand is carbonate sand... period> I am concerned about this as I am not able to set the system twice but I have no need to spend unnecessary $. Hard enough to get started as a small business. <no worries... clean, dry sand is fine or better: can be inoculated as you wish. More control> If these substrates are indeed avail for proper use in these systems what do you recommend? I have inquired as to available sands and have the opportunity to purchase many types. <calcite or aragonite would be ideal. If you go for silica based sands... you need to compensate for its lack of buffer> I have heard the "play sand " available at many home improvement stores works well. <true... do see the many message boards posts confirming this through the years> I also wondered about something like masonry sand. <eh... rather dirty. Some concern for contaminants (river dredged)> I know that they use this type of sand for playgrounds. It has a sugar sand particulate size. Any recommendations would be appreciated. One further question, I have a great number of snails in my systems that lay eggs , but never does the population increase. <some species have complicated larval cycles that do not succeed in aquaria> Any ideas? <do try for strombid snails from IPSF.com or Ceriths/cerithium species from Florida for easy to breed marine snails> Thanks for your time and I look forward to your reply. <best of luck in your endeavors :) Anthony> 

DSBs, Sand stirring and nutrients 3/16/05 Thanks for your reply. I thought I had been feeding pretty sparsely. <It could be fine feeding, but a lack of adequate water flow which allows the fecal pellets to linger. Or... bad feeding habits like allowing the thawed pack juice from frozen foods into the system> As follows: Fish: 2.5" yellow tang, ocellaris, purple firefish, 2" pajama cardinalfish. Every other day, or 2 out of 3 days, 6 or so drops of "Marine Plankton", one at a time; 1/4 to 1/3 of a thawed cube of "Prime Reef" or 2-3 large flakes of Formula 2, being careful to not feed more than they will eat in 5 min.s. I have relied on the 10 or so hermits, and 20 or so snails, to eat the leftovers. <All reasonable... easy on the hermits though - really not that "reef-safe" in the long run> My nitrates are at 0 (as are ammonia and nitrites). From that assay, I had been assuming that I wasn't having a problem with excess nutrients. <There's no mention of water changes or skimmer output. Two important issues> Here's something that's different in the last 4 or so months (tank has been operating for better part of a year total). After deciding to get into the coral business (have now had a mushroom and a Kenya tree for about 3 months--appear happy and healthy and growing, as well as a crocea for about a month after a month in QT), I no longer [move] the LR around and don't aggressively vacuum the sand bed every couple of weeks as I had been doing before I decided to add corals.  <You have no need to sand stir or vacuum as long as you have strong water movement throughout the tank (20-30X would be nice)> So, for the last 4 mo.s, I have only been able to agitate and vacuum the sand around the periphery of the tank--the LR occupies most of the footprint of the tank, except for the approx 2" space I left to get my hand in between the LR and the tank to clean the tank walls. I have a sand bed depth of 3-4 inches of med grain sand--around 2mm.  <Hmm... a bit coarse on the sand too... if the water flow is too low, this becomes a nutrient sink :(> I know from the article on DSB that is borderline, <not really... the critics of DSB neglect to emphasize that water flow makes or breaks them> but from 0 nitrates I have assumed it is working OK. <I enjoy using and recommend DSBs very much> Bottom line: is there a need, and if so how, to stir and vacuum the sand under the LR? Thanks! <No worries. Anthony>

Deep Sand Bed Good Morning Crew!  <Good Afternoon, Jeff> I would like to start by saying that I read the postings on your site daily. The information base that is provided here, for beginners and professionals, is unmatched!!  <Thank you>  I am looking at adding a 3 to 4" DSB to help control my nitrate level. I currently have 2 to 5" of crushed coral in a 55 gal. FOWLR. I vacuum twice monthly whether it needs it or not. <It always needs it.>  My question is this: Does the DSB also have to be "cleaned" like the crushed coral? Also, can I use beach sand/course shells be used if it is quarantined for at least 4 weeks? Thanks again for the services and information you all provide!!  <Jeff, I'm providing a link here on an article dedicated to DSB's. I think you will find it very informative. http://www.wetwebmedia.com/deepsandbeds.htm. James (Salty Dog)> 

Replacing CC with DSB Hello again,  <Hello Julie> Sorry to be a bother but after reading all the FAQs on DSBs and Nitrate control I still have a few questions. There seem to be a few conflicting answers throughout the FAQs and I just wanted to clarify a few things if possible. I just did a 40% water change yesterday and removed enough of my gravel to decrease the base to 1-1/2 to 2 inches. I vacuum my gravel at every water change as well in order to try and keep a handle on my nitrates. However, I understand now this is a losing battle and I'm ready to go to a DSB. <Julie, since you lowered the depth of your CC, I don't believe you gave it enough time. I would wait a little longer and do your water changes/vac gravel, and see if the nitrate comes down.>  WWM said I could leave this gravel and place the DSB on top but I've seen answers in the FAQs that say to remove the gravel completely and start anew with a DSB. I'm willing to do either, am I right in assuming removing the gravel is the better course of action?  <There is more than one way of doing things. It's not absolutely necessary to remove the layer you have in there now.>  I'm going to be using the very fine grain sand suggested by WWM. I have two questions regarding this, is it best to use a DSB in both the tank AND the sump or is their no real benefit in having a DSB in the sump if it's already in the 90 gallon tank?  <What you will have in the tank should be plenty.>  Regarding the live sand, is it best to have the entire DSB composed of live sand (like Fiji live sand if the cost is not an issue to me?)?  <I would if $ is not an issue.>  Finally, I've seen a few responses to the question of the cycling of the tank after replacing CC with DSB. At least one FAQ states that there will be cycling and spikes after doing this and that marine life will probably suffer. Elsewhere in the FAQs there is indication that this will not be the case. As described below my bio load is light. I was planning on transferring as much of the tank water as possible to a clean container along with the marine life and then creating the DSB and replacing the water and the marine life. I know you of course cannot guarantee that this will work but do you think I need to recycle the tank first before replacing the marine life or will I more than likely be ok without doing this? <Julie, live sand is much like live rock. There will be die-off and it will need to cycle. Just keep your hermits and snails in there while it is cycling.>  Thanks you so very much for your time. It's extremely helpful to all of us to have such a fabulous resource at our fingertips!  <You're welcome. James (Salty Dog)> 

Replacing CC with DSB - II Hi Salty,  <Hello Julie> Thanks for the quick reply. <You're welcome>  Not to be dense, but when you say just keep my hermits and snails in there while the tank is cycling do you mean in the tank itself?  <Yes, I cycled my last rock with hermits and snails>  Should my damsels, star and shrimp and xenia be ok in the tank or do I need to find another home for all these while it's cycling? <Yes, they will need a home.>  Finally, I read somewhere that I need 1-1/2 pounds of sand per gallon to create a 2 inch base but I'm not sure what size tank that was based on (since many 75 and 90 gallon tanks are the same size on the bottom but just different in their height). Obviously tanks differ in shape but if you consider a standard 90 gallon tank, approximately how many pounds of sand would I need to buy in order to create a DSB here? I was looking at some Fiji sand on eBay and the auction ends today but I would like to have a better idea of how much I should buy. <Julie, I would call Drs. Foster & Smith, tell them your tank dimensions, and that you want a four inch depth of sand. They should be able to tell you how many pounds you will need. (They sell the Fiji live sand also)> Thanks so much for your help?  <You're welcome. James (Salty Dog)> 

Replacing CC with DSB - III Great! Thanks for all the help. One last question if I may. When the sand eventually dissolves and I'm left with half of what I started with and I go to replace it, will I need to remove critters from the tank at that point as well due to the pursuant cycling? I know that is in the distant future (1-2 years as the sand slowly dissolves) but I can't imagine having to recycle the tank again at that time whenever new live sand is added. Thanks a million! Julie  <Julie, you won't have to recycle. Just add a couple of cups of the dry Carib Sea or whatever brand to the tank. Measure your original sand depth once it is all in, then a year later check again and see where the level is. You will probably have to do an average as the sand levels will vary along the bottom with the sand sifting crew. James (Salty Dog)> 

Sand bed grain size... Hi guys. <Stephan> Reading thru your pages I find that a lot of people set up their DSB with different grain size. Is this a new thing? <Mmm, not really... folks have used single or mixed grain sizes...> What is the real advantage over one size grain style. What two grain sizes (in or mm) would those be and how is it implemented or installed? Thanks for the clarification.  Sincerely, Stephan <Mmm, let's see... the size of individual grains dictates the amount of surface area per cubic volume... so, smaller is better by and large... Mixed sizes tend to "clog, channel" more than single grain diameter... Depending on depth of the bed, composition, angularity... most folks settle on diameters in one millimeter nominal range... In actual practice... having more of all sizes, depths generally works out... that is, if anything, folks have too little of any given grain size, depth... Bob Fenner>

- Nitrates and DSB - Hello! <Hello.> I have a question about adding a deep sand bed in my 125 gallon FOWLR aquarium that is a little over one year old. I have been doing research on your site about how to get the nitrate level down in my tank. I think I want to try a DSB, but I am concerned about maybe a too heavy bioload for it. I am so confused right now!  My tank has 1 large blue hippo tang, 1 yellow tang, 1 sailfin tang, 1 Pseudochromis, 2 clowns, 3 cardinals, 1 lawnmower blenny, and 2 blue damsels. Most of the inverts that I had have "disappeared" probably due to the high nitrate level. But I have a few hermits, a turbo snail, and one feather duster that have hung on. The nitrates are usually between 80 and 160 on my color scale. (Ouch! I know.)  <Ouch indeed.>  I do large water changes and it doesn't seem to help much or for long.  <What is a large water change for you? With any number of gallons, you'd need to change half the water to get a drop of 50% in nitrates.>  I recently added Purigen to my canister filters and it (along with a water change) has brought it down to between 60-80. I have two Fluval 404 filters on the tank and one Berlin HO skimmer rated for a 250 gallon tank. I have about 50 pounds of live rock (which I know is not enough in a tank this size). I eventually want to add more live rock.  <This would help.> I can't decide if it would be better to add more sand for a DSB or take some of the current sand out to a depth of 1/2 inch. The sand is aragonite 1-2mm. Right now the sand depth is about 1 1/2 - 2 inches. >From my reading, I have determined that this could be the reason for my high nitrates.  <Hmm... not sure I agree, unless you meant centimeters... 1-2mm shouldn't cause you too much trouble. In fact, I would examine your current filtration. More live rock would really help, but unless you clean both your Fluvals every week, I think you may find that these are what help keep the nitrates high.>  I would like to be able to eventually add some inverts such as feather dusters, anemones, starfish (no corals), but I have to get the nitrates under control before I add anything!!  <Correct.> If I do add more sand, I cannot move the current inhabitants out of the tank, so how would I go about adding it without really messing everything up?  <No easy way... you're going to mess everything up.>  Could I move my sand around to end up with it on top of the new sand or would that stir up too much stuff?  <It's going to stir up a lot.>  I figured I would get the sugar fine sand when I add more, so it would probably defeat the purpose to put the current sand on top. With the cost of adding the new sand, I don't want to do it and then be sorry later.  <Having a deep sand bed will certainly help you, but it needs to be DEEP - more than 10cm. Also, it will not be an instant cure, but will need several months to mature. More live rock will help this all along.>  Thanks a lot for the advice. Regina <Cheers, J -- >

Starting a deep sand bed sump Hello Wet Web People.... < Blundell here tonight. > I am setting up a 35 gallon refugium with 7 inch deep sand bed to couple with my 1 year old 75 gallon Berlin system tank. < Wow that is some deep sand. > It has 2-3 inches of crushed coral/shell substrate, not sure how much live rock - hope the pic gives some idea, running a Remora Pro (just got it a day ago and cant wait to see it kick in- the Red Sea Berlin it replaces was crap). The prime function of the refugium is to denitrify tank (About 15-20ppm) and any fauna that breed there in the algae, rocks and sand are a bonus to feed the mandarin and pipefish  which are going well after 3 months. < Good idea. > I have been working through the FAQ's but think I should run 3 problems by you to solve. 1) I can't find any sugar fine aragonite in Bangkok. < Don't worry, things like crushed coral are great and you don't need fine sand. > The only sugar fine stuff is possibly calcite in origin - they say its crushed mountain rock (looks like quartz to me). The next thing from that is beach sand, that while fine, is a mix of powder fine and slightly coarser grades - I have no idea where it's from, nor do they care to find out for me - bit of a worry. < Personally I would think both are safe and would use either in my tank.  However, when giving advise I would say it is safer to not use either, and to use regular crushed coral sand. > What to use guys?  Of these two options, what is the best - pro's and con's.  I understand that calcite wont buffer, but the 75 gallon tank has a 2-3 inch deep bed of crushed shell/coral in it to buffer already and my ph/hardness is always stable. < Indeed, so given those options I would use the calcite. > The deep sand bed in the refugium will be about 45cm x 40cm.  Would a mix of both available sand types work? Does Calcite reduce alkalinity/hardness? < No, I wouldn't mix them.  Also, no, calcite does not affect the alkalinity. > 2) Is it ok to keep a baby snowflake eel (6- 8inch )in the refugium - I see in the FAQ's another reader intended to do the same and it seems ok...   I intend to have just a few pieces of live rock resting atop the sand, assorted algae (Halimeda, Rhodophyta, not sure about Caulerpas) and wonder about an 1 inch layer of coarser sand on top is a good idea to prevent the eel stirring to much. I'd love to keep the eel in my main tank, but think he would eat my mandarin, pipefish and small Chromis LOL. < Well you may not see the eel very often in the sump.  But if the sump is holding 30 gals of water it is probably large enough that I would say yes you can. > 3) Should there be any clean  up crew to work the upper most surface of the DSB? < Not really.  Just a few hermits or a couple snails.  It should stay stirred up by all the pods that will be growing. > Many thanks again guys for all advice, past and present.  It's a real help. Brett Moloney Bangkok <  Blundell  > - Plenum Questions - Hello! Thanks for all of the great info! I was reading about DSB's and everywhere I am seeing stressed over 3 inches to avoid nutrient sinks and the support of efficient denitrification. I am using a plenum constructed with lighting grid supported on ? PVC caps with an overall height of approximately 1 inch. Now, my sand bed is on average 4 inches including the sand depth. The sand is a medium grain size. My local pet shop said that the grain size was specifically set up for plenums as the grains allow more water flow to the plenum. Am I creating a nutrient sink?  <You're probably on the edge of such things, but I would give it some time. We get a lot of questions from folks who have just set up such systems wondering why they have any nitrates at all, and the truth is it takes months for the plenum and deep sand bed to become fully active and working. They are not instant fixes.>  My Nitrates are 6ppm between weekly water changes, 0 nitrites, 0 ammonia, and Phosphates I am unsure of because I think my test kit is bad. Should I add another 1" of sand?  <I would, really the more the better here.>  'Cause if so my wife is going to strangle me! Best wishes, Scott R. <Cheers, J -- > 

Adding a deep sand bed ... Hello, <Hi there> I am new to the hobby with several years of freshwater experience.  I have a 29 gallon tank set up for about 3 months.  I have about 35 lbs of Marshall Islands live rock, about 1" of Aragalive substrate. 2X65 compact fluorescent CPR bak-pak2R CPR hang on refugium (middle sized) 12W on the refug, I know I need more 2 powerheads on a wave maker 1 powerhead on full time to stir the top. Tank now holds: 5 hermits 1 turbo snail 2 peppermint shrimp 1 mushroom 2 button polyp frags 1 star polyp frag. After reading all the information on Mandarins I have decided to not get one.  Even with a tank this size and the refugium it is too small, even for just one fish. I have always loved jawfish, my second choice after the Mandarin.  My question is this: Can I add more substrate to an existing tank to make a deep sand bed for that type of fish? Thanks <Yes... you set a high mark here for investigating before you buy, and higher still for the intelligence, compassion to stave off selfish satisfaction. I salute you. Bob Fenner> DSB and Clean up crews Hello Bob, <Michael> Congratulations on your 'Reef Invertebrates - an essential guide' book 1, an excellent read and I can't wait for book 2. <Us neither... turns out we can't cram Reef Fishes into one 400 page volume... so it's being squeezed into two... along with a few necessary survey pieces on selection, quarantine...> I have spent the last 6 to 8 weeks updating myself with all aspects of reef-keeping, reading lots of literature, surfing and frequenting bulletin boards etc. I had spent a lot of time getting ready to set up a reef system 12 months ago, but circumstances changed and I was unable to until now. <Outstanding> I have ordered my set up last week, and this will be installed in 2 weeks (the waiting is killing me). I have gone for the biggest I can afford and consists of the following: 66"Lx26"Dx28"H tank, central weir. 660l. 145 Imp Gallons after displacement 42"Lx18"Dx18"H Sump with built in top up compartment 105l. 25 Imp Gallons for sump and 50l. 12Gallons for top up Total 765l. 170 Imp Gallon system Eheim 1262 return pump Deltec TS1060 skimmer TS24 stream kit with a 7095 controller 1/2" sand bed in main tank 62kg Fiji LR Arcadia series 3 triple 250w halides 14,000 Tunze 3155 universal Osmolator <Very nice> The fish and corals I would ideally like to keep are as follows LPS , Hammer LPS , Anchor Coral, Euphyllia ancora LPS , Branching Hammer, Euphyllia parancora LPS , Frogspawn Coral, Euphyllia divisa LPS, Torch Coral, Euphyllia glabrescens LPS, Plate Coral, Heliofungia actiniformis LPS, Disk Coral, Fungia scutaria LPS, Pacific Rose Coral, Trachyphyllia radiata LPS, Open Brain, Trachyphyllia geoffroyi LPS, Trumpet Coral, Caulatrea furcata SPS, Star Column Coral, Pavona clavus LPS, Bubble Coral, Plerogyra sinuosa LPS, Elegance Coral, Catalaphylia jardinei Softie, Pulse Coral, Xenia lamarck SPS, Table Acropora, Acropora anthocercis Zoos Montipora Feather Dusters FISH Regal Tang Yellow Tang Pair Common Clowns dot dash blenny Anthias Scooter blenny Wrasse not sure which yet I guess I should get to the point of the mail, which is the substrate for my display tank, sump and what should make up my clean up crew. As you can see from above, I am only going for a 1/2" sand bed of CaribSea sugar sized aragonite sand. Is this OK as I don't like the look of a DSB in the display tank, this is more for aesthetics? <Should be fine... do be aware in your wrasse selection of genera that "dig"... need for a bed of substantial size for them/it> What should I put in the sump, would a DSB be OK (have heard they can crash) if so how deep is best and do they require lighting? or any special care? should I anything else in there. <I would have some lighting... and algae, live rock there in addition to the DSB... not likely to crash> My last questions are about a clean up crew, I was all set to get a mixture of Red and Blue Legged Hermits, Mithrax crabs, Turbo's, super turbo's, Nassarius, Ceriths, 2 or 3 common Sandsifting sea stars (LFS stated 3 for my size tank, think that's 2 to many), conches, sea cucumber and sea hare. But I keep getting mixed reports about hermits eating snails for their shells, but this can be overcome by ensuring lots of spare shells are kept in the tank. Is this true or should they not be trusted. <I am NOT a big fan of so-called clean up organisms... and encourage you to shy on the conservative side in their use, number... I would leave out the Mithrax/Mithraculus crabs entirely... and likely all but the "blue legged" hermits... easier to add later than to try to extricate such animals> I am also not sure about the number and type of sea stars and whether the sand in the display tank is deep enough for them. Conches, sea hares and cucumbers are they OK in this size tank, should be left until the tank is more mature, if so how long is that? <Six months or so> Bob, if this was your tank (and you were a newbie like me), which types would you have in there, how many of each type and how many of each type would you put in and when would you put them in. How long after the tank has cycled should I put the first batch in and when should I add the non-snail/crab inverts? <I might add some of these listed cleaners... a dozen or so individuals... on the establishment of cycling... with all live rock placed, no ammonia, nitrite... the evidence of some algal growth... but wait on adding more till after some of the fish life is established> I realize there are a lot of Q's there Bob, and can appreciate you may not have the time to answer all of them. <Quite a few> But thanks all the same from sunny old England. Kind Regards Mike <Cheers, Bob Fenner>

DSB with high nitrates Hello all, I have a 75 gal. saltwater FOWLR tank. It has about 80 lbs of live rock, a 4" to 6" DSB, 10 gal. sump with an AMiracle protein skimmer, and a Rena Filstar xp2 canister filter which I run carbon and phosphate pads along with the sponge pads. For fish I have a 5" Picasso trigger, 5" yellow tang, 5" maroon clown, and a 3" volitans lionfish. I have had the tank going for almost a year and have not had any problems with nitrates until lately (within the last month). I have an idea that my tank is overstocked, but why would the nitrates be low for so long then all of a sudden go up? <Mmm, very likely (well, most likely) has to do with interaction with more easily soluble components of your substrate... they've been absorbing, completing more...> They always stayed at less than 5ppm but now are going up to 20 ppm consistently. All the livestock (except for the volitans) have been in there pretty much from the beginning. I got the volitans for Christmas after my Radiata (who was about 6") choked on a turbo snail shell. <Not uncommon... Lions will/do ingest most anything!> I do also get red slime and have lots of hair algae within the last month. Could my DSB be going bad or am I destined to do many more water changes? <Maybe both, perhaps neither... have you considered adding a live sump/refugium?> currently I do 20% twice a month. I also have a 45 gal reef tank using a Jaubert system with soft corals, 2 clowns, a small regal tang, algae blenny, and mandarin. The nitrates have been below 5 ppm always. What I am planning on is to move the reef tank over to the 75 gal. and move the inhabitants from the 75 to a 180 gal. in the spring, but for now I am kind of baffled and thinking of switching the 75 gal. over to a Jaubert system to possibly help with the nitrates. Any help would be happily appreciated and taken seriously, even if its something I didn't want to hear but know to be true. Thanks <Mmm, am very tempted to encourage you to join all these systems together... you would find the nitrates greatly reduced in short order... Bob Fenner>

Playing With Sand (Deep Sand Beds) Hi crew! <Hello there! Scott F. with you today!> Firstly, thanks to Matt for answering my last queries! <Attaboy, Matt!> Just been speaking to my LFS and wanted a second opinion on a couple of things. I've got a plenum in my sump with 4" of aragonite, and about 3" of aragonite in the open/visible parts of my display (live sand added over dead rock when tank first set up so it will have sneaked into gaps creating an uneven bed). I'm wanting to up the DSB to >3" and also get some in the "caves/hollows" so that the whole base is this deep. I was told that it was detrimental to have a DSB when I've got the plenum in the sump and I would be better taking the DSB out completely i.e. <1/2". <I'm not sure why this would be considered detrimental. Properly maintained plenums or "static" DSBs are beneficial. Perhaps it's redundant to have two sand beds, but I am not sure what the disadvantage could be, short of taking up lots of space...> It cost me a fair bit of money (over 100lbs of sand) so don't want to do this in a hurry, but then don't want to buy more sand if it is detrimental. The argument was the risk of ph crash with the DSB due to detritus build-up - i.e.. living on a knife edge where something could tip it over to a point where I couldn't react fast enough to fixing it. <I think that is a speculative argument based on largely anecdotal evidence. In fact, thousands of hobbyists, myself included, have maintained DSBs for years without any problems whatsoever. I think that the "DSB becomes a nutrient sink that will crash your tank" argument is based upon several people having bad experiences and then going wild on the popular reefkeeping message boards touting the detriments of DSBs. A properly developed, well maintained DSB in a tank with overall good husbandry techniques is an excellent way to successfully maintain a reef system. The key is attention to proper husbandry. DSB's are not a miracle, but they are not recipes for disaster, either. Attention to water quality, feeding, etc., vital in any system, are also critical in a DSB-based system.> I was also told that I shouldn't use aragonite in the sump as it will gradually (within a year) bond into a solid lump. <Well, this is true if you do not stir it up a bit once in a while. This can occur in the display tank as well as the sump, BTW.> I've got a spare 20lb bag of LS to add, but I've been told that it is dangerous to add LS to a stocked system as it would swallow up the oxygen. <Well, I'd add it gradually. Any change made to an existing system should be made slowly, and adding more live sand is no exception to this rule > It all threw me somewhat! <I can imagine!> Bought some Kalkwasser whilst there for my top up but wasn't sure how (or when) to use it. My calcium is about 350? Should I be adding it? On the pot it says to mix up separately and drip siphon in. I can't work out how this applies to my top up tank. Do I just pop the required amount straight into my top up (it's heated and aerated) as it is added very gradually to the tank (i.e. a week+) by the level controller? <Well, there are a number of different ways to add Kalkwasser, ranging from exotic drip systems to simply dumping in the Kalkwasser in a "slurry"; the amount you need to add is based upon testing. Do read up about Kalkwasser additions right here on the WWM site, or in Anthony Calfo's invaluable "Book of Coral Propagation", which discusses the simple "slurry" technique in greater detail.> Thanks again in advance. Peter <My pleasure, Peter. I'm glad that you are skeptical of some of the advice that you hear. If you have a doubt about any advice you receive (including ours!), it's always a good idea to get a second (or third) opinion if you have doubts. Good luck! Regards, Scott F.> Screen between sand layers? Dear Crew: Last Sunday I put sand (approx. 4'') in my new tank. I got so excited doing it that I forgot to place the mosquito screen between the layers (to prevent the sand sifters from disturbing the DSB) as I was going to :) I'm planning to have some sand-sifting snails and possibly a starfish in that tank. Should I take the sand out and start all over and if I don't will the snails and starfish defeat the purpose of the sand bed by turning it upside down? << I wouldn't worry about it.  With 4" you should be fine, they won't sift that far down. >> Thank you very much for all your help. << Don't worry, just take it slow. >> Peter <<  Blundell  >> Removing a DSB? 11/30/04 Hi Crew, <howdy> Searched your site and did not find an answer to this question: I have found that I am now suspicious of my 3 year old DSB.   <likely should not be... if you have had proper water flow (20 X or so) and good nutrient export, DSBs are low maintenance and tremendously beneficial> I have a 110g reef with 1-Yellow Tank, 1 Blue Tank, 2- Clowns, 1-Watchman Goby, 1-Neon Goby, 1- Dottyback, 2-Cardinals, 3 6-10" BTA's 1 SPS and 1 LPS.  This may be overstocked?? <nope... no worries here> I am not sure, with a EuroReef CS8-2 skimmer.  It has been fine until recently: Nitrate was 0, now 5 and I have been very working hard lately to keep the DSB clean from diatoms/brown algae on the surface and also between the glass on the front and sides. <weak water change schedule catching up with yo more likely. 10-20% weekly or at least 25-30% monthly?> Nothing has changed (water source, filtration, lighting, etc.) except the age of the DSB.  Now it is a real hassle and I like clean sand.  I want to take the DSB out leaving 1/4-1/2" of sand, is this ok to leave the bottom layer of sand?   <yes... but you lose a tremendous nitrate removing potential (the DSB)> How do I remove the sand with hurting the livestock?   <manual labor... drain away clear water, livestock and rock and remove the little bit of water and all sand left. Replace and top off. several hours and a sore back later you are done> Also can I save the used sand for when I get a larger tank, which will be soon? <indeed... give it a good rinse, keep it dark with high water flow in a garbage can/other aquarium, etc> Thanks for the help, you guys are the best and the main source of information that I trust. Rich <best of luck/life. Anthony>

Re: Removing DSB Hi Anthony: <He's out till 12/12...> <weak water change schedule catching up with you more likely. 10-20% weekly or at least 25-30% monthly?>!!!!!!!!!!!!!!!!!!!!! Please tell me that you mean for a short time!?!?  I couldn't afford the salt, water (.50 a gallon) or time!?!?   <Please read here: http://www.wetwebmedia.com/scottsh2ochgart.htm and the Related Articles, FAQs (linked, in blue, at top)> I currently do 10% a month and also replace about 10-15 gallons a week through evaporation (open top, MH lighting) which costs me quite a bit in water as it is.  Will I actually have to change 25% of a 265 gallon tank (which is what I plan to upgrade to soon) with the same livestock?  If so I may stick with the 110g. <Better to do more frequent, less volume changes... but I'd be looking into making my own change water...> Thanks for the advice I will reconsider removing the DSB. Regards, Rich <Bob Fenner>

Re: 375g setup Hi Anthony, <Out till 12/12> Thanks for the tip - I will follow up with him. When you commented "you don't follow", I was asking if switching the 2 DSB's would have any effect or make a difference (i.e. Thalassia in the refugium with sugar fine sand and the Chaetomorpha with fine sand in the tank). <Might indeed make a positive difference> Also, I wondered if this was going to be quite enough tank turnover...other than sea-swirls is there anything else that can perform their function? With their 1" max input it's going to take a lot of them ($$$$). Would I just plumb some of the additional returns as "direct" and aim them away from any specimens to avoid uni-directional flow ?            thanks,               Greg <Best to make, place a manifold of a few discharges... with one through-put to a few, or even an "over the top" arrangement to return water from a strong pump source outside this size system. Bob Fenner>

Deep sand bed I have read much on the subject of Deep Sand Beds but nothing that puts it all in a nut shell. Is there anywhere I can look that shows the exact  complete construction of one of these? I have read miles of varying opinions on this subject, so something solid would be quite refreshing.  Actually with as many times you have been asked about this, I am surprised that you have not pointed these people to a complete answer  somewhere. <Take a look here  http://www.wetwebmedia.com/deepsandbeds.htm, Great article by Anthony Calfo.> 3" 4" 5" (with 5" looking like the target) 6" 7" more? Water in plenum starts to heat up causing slow circulation? What is  the normal circulation equal to? (No need for a pump?) <I'm a little confused about what you are asking here, can you please clarify?> What if I wanted to assist this circulation by sucking out some of the  water under the plenum with a pump, maybe create a drip or something? My sump is a 55gal glass tank that sits on a cold tile floor on its plastic  framing.  Will the lower floor temps affect the warming under the plenum creating no circulation? What should the difference in temperature be between the under plenum and  room ambient or ambient temperature of the free moving water in the sump?  Should I add a heater under the plenum to assist circulation? Would it be to my advantage to create a deeper plenum? (a larger void under  the sand. a larger under sand water pocket) <I don't think a heater under the plenum would be helpful.> I am trying to get a good comprehensive understanding of what's going on so that I can assure the effectiveness of the process.  <Definitely take a look at the articles on setups. I think you'll find them very useful> Many Many thanks for all your help.  This is the first time I have ever asked a question here. <You've done well! good luck, MacL> Sincerest regard, Paul

DSB Materials - More Questions >Marina, >>Hello Dan. >Assuming the mineral analysis from the quarry shows acceptable levels of undesirable compounds, I'm going to try the limestone, but I'll have to screen it once to get the desired maximum particle size, then again to screen out the pieces that are too small.  What should my max and min particle size goals be? >>I've actually seen DSBs with rather large particles (one DSB which was working *very* well had fine gravel sized particles - over 3mm), as well as those that could only be called silt.  I wouldn't worry too much about screening out small sizes, let water movement handle that, nor large except for aesthetics.  1mm-3mm is what I'd call "standard", though I can't say it's written in stone (no pun intended). >Of course, I plan to wash it thoroughly, soak it in clean water with frequent changes until the pH is stable at 9.0 or less (according to WWM) before slowly introducing it into the aquarium.  Dan >>You're on the right track, and unless the limestone is heavily occluded with other materials, doubtful if it's being quarried (I assume for building), then I suspect it should come back with pretty good results.  Marina Deep sand bed depth? Hello, I have a 29 gallon sump for a 50 gallon main tank.  In the sump, I have 4 to 5.5 inches of CaribSea aragonite sand.  My nitrates typically run 0.  I've read repeatedly that it is preferable to have 6 inches or more sand for denitrification.  << No, 3 inches is fine, maybe even 2. >> My question is, would it be okay to add very fine oolitic Aragamax (sugar fine) on top of the CaribSea aragonite sand (.5-1.7mm)? << Yes, and it will slowly works its way to the bottom. >>  I would add it at .5 inch per 2 weeks as I've read that is sufficient to allow organisms to inhabit the newly added sand without suffocating them.  Alternatively, would it be preferable to add more CaribSea aragonite sand (the same grain size as what is already in my sump) << Sure you could.  But I wouldn't.  If everything is going well, then don't be adding things.  And 4 inches is deeper than many tanks. >> to get up to the 6 inches-- rather than the smaller grained oolitic Aragamax?  Or does it matter? << In your case, I don't think it would do any good. >>     Also, I've read about the importance of keeping the sand level an inch or less in the main display if a DSB is used in the sump. << I have no idea why.  I'd say it is better to have your display tank with sand deeper than your sump, so I don't know why anyone said otherwise. >> I've read the warnings, but I'm not clear on the danger(s) of having say a 2 inch sand bed in the main tank.  What might happen? << The problem is that your sump may not be big enough (surface area) to complete all of the necessary denitrification.  So having a DSB in your display tank can really help out here. >>  I'm asking because my sand bed (CaribSea aragonite .5 to 1.7 mm) in the main tank varies from .5 inches to probably 2 or 2.5 inches in one area under some live rock.  Do I have to  change this or am I okay? << I think you are okay, but I'd add sand here before I'd add it to the sump. >>   Thank you in advance for your help, Gary <<  Blundell  >>

DSB Materials >I want to switch to a DSB, but the expense of aragonite sand at roughly a dollar-a-pound is excessive.   >>I can't say I disagree! >I called Southdown.  They no longer produce the Caribbean play sand, apparently the result of a corporate merger.   >>I can think of a few people who will be sorely disappointed. >Is there a suitable inexpensive substitute for aragonite sand as a marine substrate?   >>Nothing that I can reliably advise, I'm sorry to say. >I'm assuming DE is a no-no due to the silicates and small particle size.   >>No, the silicate is not a problem, neither is the particle SIZE.  It is particle SHAPE that is at issue, silicate-based sand/substrata can be *quite* abrasive, with sharp corners that are not conducive to the activity we seek from certain flora/fauna when setting up DSBs. >We have a limestone quarry nearby, but I'm not sure whether limestone sand can't be leached to an acceptable pH for marine aquarium use. >>Well, limestone is what it is because it's essentially compressed coral skeletons.  It is calcareous in nature, and therefore should both buffer strongly and provide an acceptable pH for marine or similar use.  As long as it's clean and has no other minerals that CAN leach undesirable compounds in saltwater, there should really be no problem.  A test run would be advisable if you're really in doubt.  Marina

Deep sand beds and alkalinity Thank you again!!! I think I might agree with on the DSB in the sump. (of course my sump is not big enough so I will have to change things around a bit) Wish I would have found you guys 9 months ago. I was also thinking about what you said about adding sand to the front of the tank. Do you think it would ok to siphon my sand from the back of the tank (live rock is in the middle of the tank so I have room in front and back) and add that to the front of the tank. << I wouldn't siphon with a deep sand bed. >> Going from about 3" in the front to nothing in the back? As far as my Ph goes it seems to stay consistently at 8.3 (never checked it at night) I have also added SeaChem's Reef Builder about 5 times in the last month (1 teaspoon) to bring my Alkalinity up. It really has not moved much . Do I need to be more aggressive, I didn't want it to raise too quickly. << Hmmm, not sure.  I'd consider using one part of a two part solution (like B-ionic) to raise the alkalinity.  But go slow. >> Sorry about all the questions but it seems the more I learn the more confused I become! << That goes for all of us. >> <<  Blundell  >>

Sand types of depths Thanks for the reply Blundell!! << That's why we're here. >> In response to your questions about the deep sand bed, no, I currently have crushed coral for the substrate.  It is about 3" deep on average. << Just what I would recommend. >>  I also have about 12 lbs of live rock, coral skeletons, large purple barnacles, one red lava rock, and some green sea grapes.  My goal is to add about 40 to 50 more lbs, but it will be awhile.  I did a 50% water change last night and am planning on adding the fish back in today.  PH is at 8.3, Ammonia - 0, Nitrites - 0, Nitrates - 20-30ppm as of last night.  Going forward I am going to do weekly water changes, at about 5 to 10 % each time.  This will mainly be to vacuum the crushed coral to keep the nitrates down.  I have read more on the deep sand bed and have a question.  Can I use beach sand as the sand bed? << Yes, but I don't like the idea of vacuuming the sand.  If you do, only clean the very top layer (top half inch) and don't disturb the lower areas. >>  Or should I buy what is at the LFS? << Well I believe the LFS sand to be clean and free of contaminants.  The beach sand is great if you are sure it meets those standards. >> Thanks Jeff <<  Blundell  >> DSB & Calcium Hello WWM, <<Hi there>> I have two questions the fist being. I have a 90 gallon reef tank that has been set up for 9 months. I have about an inch of live sand as a base. I was wondering since I have quite a bit of live rock and soft corals, is it too late to add a DSB? Everything in the tank is starting to look really good and would not at this point want to mess it up. I'm not sure if moving all that rock with corals attached would cause havoc on them or would it be worth the risk from the long term benefits? Also If I use sugar sand can I pour it over my live sand that is a little more course? <<Fishkeeping is subjective, so the answers to these things depends on who you ask :P I have had no problems with deep sand beds. Thing is, they DO need to be maintained (water testing needs to be done regularly, so you can foresee any pH etc, problems and remedy them) You don't want your sand bed to become supersaturated with organics without your knowledge. There is plenty of opinion in forums here about DSB's, read on! If you have a sump, you can put your Deep Sand Bed there. That way you will not have to mess up your reef structure: this is beneficial for a few reasons: the ease of installing it, maintaining it, an removing it if you change your mind further down the road. Another idea is if you have enough open space at the front of your tanks rockwork, you can try adding the sand at the front of the tank only, and just letting it drift back in between the rockwork. If you add sugar sand, you will not need as deep a bed, three to four inches should be more than sufficient, and you can stir in gently into your older sand. Once you do add the new sand let it sit, do not disturb it unless it's necessary. It will take a while before the new sand bed becomes a nitrate reducing machine, so be patient. I prefer the idea of putting it into a sump, though. Just seems easier.>> Second question is about my calcium levels. They seem to be quite high around 550 with Alkalinity at around 3.0 -3.5. I was trying to get coralline to grow I might have over done the Calcium a bit. Even after three water changes using Tropic Marin salt the levels have not come down much. I was using Seachem's Reef Complete & Reef Calcium. But I have not added any of those supplements for over a month? <<First, you might want to try a different calcium test kit, just to verify your previous results. And take a water sample to your LFS so they can test it also, and compare results with yours. Your alkalinity is too low. Is your pH also low? Is your pH stable? Does your tank have good circulation? All things must balance. Please do some more water changes, to lower your calcium to approx 400-450 max, and use your products to keep your Alk and pH stable, if necessary. And, as always, do so gradually.. Please make sure of your test results before adding anything. You should use good test kits, and you should be as precise as possible when doing them. Keep a written record, and remember that a relatively new set-up such as yours can show normal fluctuations. Just be sure they are accurate ones, so you can react accordingly. Keep on testing :) -Gwen>>    Thanks again for your help! <<Welcome>>

The Old "DSB Crashing" Query Dear WWM crew, <Hello! Ryan with you today>   I really apologize for asking too many questions, but I have no one else to ask...<That's kind of sad!  Happy to help> I have a 3" to 4.5" sandbed that consists of a 1" layer of carbonate sand that is so fine it is almost like baking soda. <Great> On top of that is a 1.5" layer of aragonite that is between .05mm to .2 mm, and finally a .5" to 2" layer of .2mm to .5mm aragonite. The bottom two layers are over a year old and the top layer is a bit over 2 months old. <OK>   During a pre-vacation 2 X 25% water change, I decided to vacuum the top half inch layer of sand for the first time ever. Most of the sand yielded a yellowish muck that made the drained water look like a 10% Kent Marine Microvert solution in water -proof that my DSB is accumulating nutrients at the very least -my nitrates tested zero yesterday. <I'm sure you stirred up quite a scene> Sand from the rear corners of the aquarium however was pitch black just below the surface and I decided to vacuum off the whole lot on one side but left the other side alone, only slightly disturbed. The sand here smelt like hydrogen sulfide!!! I guess I need more circulation in the corners. <Yes, and perhaps a better skimmer> At this point, can I save my DSB by removing all the black sand and replacing it with new sand and adding more power heads pointing to the corners? Or should I leave it alone and just add the powerheads in the middle pointing to the corners? Currently I have three power heads in various corners pointing towards the center. <I'd use a powerhead that is designed to move lots of water, with a soft touch.  Check out Tunze Streams, or Rio Seios.> As for routine maintenance in the future, I intend to vacuum the top .5" regularly, removing it and replacing it every six months. Any comments on this one? <Increase overall sand depth to 6+ inches of powder fine sand, never touch it again.  The most sandbed duty you should need to do is to add a fresh handful from time to time to keep your bacteria populations in check!> I can't thank you guys enough!!! <No problem! Good luck, Ryan> Narayan

DSB Cleaning Question (10/8/04) Hi folks, <Steve Allen with you tonight.> I have a 54 gallon corner tank, 50 lbs live rock, on a sand and crushed shell bed about 2 inches deep. <This is a difficult depth--too deep to easily maintain and too shallow to provide anaerobic denitrification.> Water quality is good, specific gravity, pH, alkalinity, etc., are good, things seem to be okay. The tank is almost one year old, and there are all kinds of neat things growing up out of the rock - lots of small feather dusters and the like. At this point, we've got a yellow tang <will outgrow the tank--needs a minimum of 75G>, two ocellaris clowns, and a blue damsel, as well as crabs and snails to help keep things clean. The fish are nice and healthy. I'm using a TetraTec PF300 filter and a Berlin Airlift skimmer (I'm thinking of replacing it with a Fluval 200 or similar filter at some point). <The skimmer? Are you suggesting replacing a skimmer with a canister filter? Not a good idea. Canisters need to be cleaned at least once a week.> We'd like to add another couple of damsels <Probably won't work. These are mean, territorial fish. Someone will die.> and perhaps a blue hippo tang in the near future. <No. Tank way too small--this fish needs minimum 125G, preferably more.> Any other suggestions on fish to add? <You should buy Scott Michael's "Marine Fishes" and study up. How about a Flame Angel? Or a Hawkfish. Trade the Tang back for credit toward both. Royal Grammas are nice too. Lots of better choices than the ones you have mentioned.> Recently, I stirred up some of the bed, and noticed that a murky, dark gray cloud came up from underneath. I suspect that I may not have the right critters to dig around underneath, and that as a result there may be a lack of oxygen getting down into the middle and bottom of the bed. <Actually the purpose of a DSB is to create the anaerobic (no oxygen) conditions that foster the growth of bacteria that convert nitrate to nitrogen gas. Unfortunately, yours is a depth that does not accomplish this and is difficult to clean.> What would be the best way to deal with this? <Deeper sand--4+ inches.> Should I go ahead and somehow manually stir up the bed from time to time to get this murky stuff filtered out, or do I need a different kind of critter (we have a sand-sifting sea star, tried to add a second one, but he/she died after a short time)? <These are overrated and unlikely to be able to survive in a smaller tank like this. For stirring the surface, I like Nassarius snails and maybe a burrowing fish like a Shrimp Goby--one has to be sure the rocks are sitting on the glass, not the sand so the Goby cannot undermine them and collapse the structure. Serpent stars are good detritus eaters.> Should I use a siphon to suck out the murk as I'm doing the next water change? <Gentle vacuuming, but not too deep.> Thanks, Otter in Ohio <I highly recommend that you read the FAQs about sand beds. Consider also buying Bob & Anthony's "Reef Invertebrates" for it's excellent chapter on DSBs. Then choose how you want to proceed. Hope this helps.>

No More DSB? This question is for Jim. Yesterday (09/13/04), in one of your responses you stated that you are finished with DSB's and are going to stick with a shallow sand bed.  Could you share your reasons for doing so because I really have only read beneficial rationale for keeping a DSB.  It would be nice to be able to consider some of the downsides of a DSB. >>>Hi Corey, Some reefers are steering away from DSB's, and I may be joining their ranks. While it was once thought that certain functions take place only in the deeper parts of a sand bed, it SEEMS as though this isn't really the case. Apparently, a shallow sand bed is just as effective. I say "apparently" because this seems to be what recent empirical data indicates. Sooner or later it seems, most sand beds crash. Dr. Ron Shimek says no, not if properly maintained. The bottom line is, the jury is still out on this issue. Other reasons, they take up space in the tank, and when the day comes that you have to move the tank for any reason, moving a sand bed is a HUGE job all by itself. This I know. :) Really, I'm just over it, and I see many successful tanks without them. When will I start pulling mine? Who knows. :) I'll never go bare bottom, I hate that, and I still need a bit of sand, maybe 2" to sit my clams in. Jim<<<

- Almost a DSB - Dear crew, Thanks for such a great site. It has answered a lot of questions for me. There is so much info here that I cannot find or have overlooked the info I'm trying to find. I currently have a depth of about 2.5 - 3 inch depth of CaribSea Seaflor Special Grade Reef Sand: 1 - 1.7mm diameter grain size and I want to increase it to around 4 inch. <If I could encourage you to possibly work this up to about six inches... four doesn't really qualify as "deep" and might cause more problems than it will solve.> I need to know if I should stay with this same grain size or if I should add sugar fine grade to it and if so how do I best add it. <Personally I like to have a mix of grain sizes, including fine... and in order to get the benefits of a deep sand bed, a good portion of it should be "sugar" sized.> Thanks for all your help Mark <Cheers, J -- >

- 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 -- > Deep Sand Bed Without Deep Problems Hi Scott <Hello again!> How are you doing? <Doing fine, thanks!> I introduced some extra sand in my tank converting my existing sand bed into a deep sand bed. One problem; well I think it might be a problem in that I had a lot of crushed coral mixed with my sand bed which basically would have been impossible to remove unless I stripped the entire tank. I added the new sand on top of this layer of crushed coral and existing sand. I am thinking that the crushed coral might be an impediment, blocking all the live media from coming up form my old sand to the new sand that I have added and that all the dirt will remain at the bottom layer of sand not allowing DSB to perform the filtration that it should. Does this make sense or do you think that it will be ok? <Well, in a deep sand bed, you would not want to use a coarse substrate material. Many of the more nasty outbreaks of Cyanobacteria that I have seen developed in tanks dominated by coarse substrates like crushed coral. If a DSB is your goal, I'd opt for a very fine material> Some of my live rock also got covered with sand with the addition of the new sand will this be ok for the week till I get a chance to reorganize rock placement on the weekend? <Should be okay for this length of time> Please share your thoughts on my above concerns. Thanks Again Ziad <As above- if you are going deep. I'd use a very fine substrate. Best of luck! Regards, Scott F.> Sand bed and pH questions? Hello all that keep me sane, << Blundell today. >> Just a few quick  questions. Will crushed coral substrate keep the PH in my salt tank at a desired  level ? Like maybe 8.2 << It helps, but good salt mixes and proper (meaning when needed) additives are also important. >>? Is crushed coral suitable for a  DSB ? << It is the best choice if you ask me. >>   If so what would be minimum depth ? << Well you specified you wanted a DSB so I'll say 3 inch min and 4 inch is best. >>  How about 1.5  to 3.0 size rocks ? << Rocks? Hmmm, well I would just buy crushed coral because with all the money you invest in your aquarium it is a minimal addition for something so great. >>   What do you think about fine grain sand at one  end and crushed coral on the other for a DSB ? << I would rather see you use fine grain on the bottom half, and crushed coral on the top half.  This is actually very popular, and seems to be the best way to go (so the current trend is). >>  Will Tufa rock raise the PH  of salt water ? << No. >>  Will low PH keep my Copperband butterfly from eating  ? << Sure, if it is low enough. >> I know you've caught on by now so here's the story. 1 Copperband 2.5  inches long in a 10 gallon quarantine tank.  No substrate, bare bottom, 1 mini penguin filter and heater, room lighting only. All tests are good except low PH, around 7.7 . I'm not adding any medication or supplements to the water  but changing out about a 1/2 gallon a day. << With a two gal water change you could probably fix the pH problem. >>  There is also a good piece of live rock in there from the main tank which he picks from. The LFS said the butterfly was eating Cyclop eeze but I haven't seen him eat anything. << That pH is low.  I would be debating if your quarantine is now doing more harm than good.  I'd be tempted to throw him in the tank, or at least do a large water change in the Qt. system.  That water condition doesn't sound like it will help him make the transition to your tank, just add stress to him. >> How long before he dies of starvation ? << Well a couple of weeks, but of stress maybe sooner. >> The fish looks as good as he cost and I don't want him in the main tank until he's eating or passed the quarantine test.  If I try the freshwater clam trick will that foul the  water to fast ? << I don't know what that is. >> By the way I control the light cycle with the room lights  on the same schedule as the main tank.    Sorry about the long  description I just wanted an expert opinion. << Sorry you got me today. >> Thanks and lets keep those  books coming. << Will do. >>   <<  Blundell >>