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FAQs about Deep Sand Beds, Depth

Related Articles: Deep Sand Beds, Marine System Substrates (Gravels, Sands) by Bob Fenner, Marine Substrate Options by Sara Mavinkurve, Live Sand, Biological FiltrationBiominerals in Seawater, Understanding Calcium & AlkalinityNitrates in Marine Aquariums

Related FAQs: DSBs 1, DSBs 2, DSBs 3, DSBs 4, DSBs 5, DSBs 6, DSBs 7,  & FAQs on: Rationale/Use, Dangers, Physical Make-Up, Biological Make-Up, Size, Location, Conversion to/from, Maintenance/ Replacing/Adding To, & Live Sand FAQsFAQs 2Live Sand 3, Identification, Selection/DIY, Systems/Placement, BiotaMaintenance, & Marine Substrates, Mud Filtration 1Live Sand, PlenumsNitrates in Marine Aquariums, Refugium Substrates/DSBs,

Take care in choosing substrate depth that matches your livestock... A Gomophia here.

Very Deep Sandbed; Mantis sys. f'       4/16/13
After keeping several stoma<to>pod species most of the local shops know I'm about the only person in the area who keeps them.  Friday I got a frantic call from one of the guys and the wholesaler decided to toss in 2 stoma<to>pods
into the order.  I drove out and saw they had an adult smithii which I happened to be looking for and had a 10g already being prepped so I grabbed him.  The other was small zebra about 3 inches long which I was hesitant to take since I didn't have a tank that would really be able to handle it's unique sand requirements.  After hearing my issues with talking about it I was cut a good deal on a 47g column which as it grows I can most likely plumb into a sump for extra water volume.  It didn't really hit me how much sand
<And mixed rubble... need for stability/tunneling>

would be needed to setup for this thing and according to the sandbed calculator on reef central said 375lbs to hit the 20 inch mark.
<Mmm, I'd stop at eight inches or so>

 I've never had a sandbed remotely this deep and I'm starting to wonder will the tank be able to handle that much sand? 
<Is dangerous... too heavy and trouble w/ not enough water to filter, offer for gas exchange>
Water weighs a lot as well so I think I should be fine, but after doing some Google searching I can't really find too many (any) setups that have this sort of sandbed that aren't part of larger custom systems.  Since I'm in an apartment I just want to cover my bases before risking a blowout and possibly having to break down all my tanks.
<I agree w/ your concern... would limit; no need for more>
<Welcome. Bob Fenner>
Re: Very Deep Sandbed      4/16/13

Yeah I have varied grade sand from sugar fine to some coarse stuff and some crushed coral to allow for stable tunneling.
<Ah good>
  Why stop at 8 inches?
<Is sufficient depth, and for the size, shape tank you mention, leaves enough water volume>
 I mostly ask after reading care for zebras from Dr. Caldwell and talking with Kharn who  keeps some 20+ species including L. malculata and both say to do a sandbed 1.5x the animals length which can reach 15 inches.
<... Won't get this larger here>
 One of the setups mentioned had the 20 inch sandbed and only a few inches of water.
Right now the specimen is only about 4 inches, but I have concerns about trying to layer sand up over time as it grows trapping a lot more waste in the sandbed versus starting with a sandbed that will support an adult.
<... Up to you (of course)... have stated what I would do, and the rationale for it. BobF>

Recommended substrate for competing objectives (DSB, avoidance of  cloudy tank with stirrers)    7/3/12
Crew, I am planning a 200G FOWLR with: Porcupine puffer, Wrasse (Coris Gaimard or Choerodon Fasciitis), PYTB Tang, Eibli Angel, Bicolor Goatfish, 2 Maroon Clowns, Eibli Angel, and 3 Engineer Gobies.
As you can see, I have selected some functional fish in the tank, particularly with substrate stirring. However, I don't know if/how to balance the desire for a DSB (for NNR), using the finest substrate possible, with the prospect of a cloudy tank due to the engineers, goatfish, and wrasse. Can you recommend a substrate and depth?
<A fine... 1-3 mm. mix of aragonitic or coral sand... rinsed well (in aliquots of 5-10 pounds in a swirling garden hose discharge in a clean "pickle bucket")... as deep as you can stand... 3 plus inches>
Also, is there risk that these fish will stir the deeper pockets of the DSB, causing problems (nitrates and other toxins due to disruption of DSB activity)?
If so, should I instead plan the DSB in the refugium and target a lesser depth, and coarser, substrate?
<Best to have fine/r substrate in both... which is what I'd do>
Thanks, Dave
<Welcome. BobF>

Sand Bed Question (Placement, Depth'¦Lighting Too!) -- 05/21/10
Dear WWM crew,
I wanted to compliment your time consuming devotion to providing insight for those of us less educated in the ways of taking care of aquatic life.
<<Many thanks'¦and we do hope the latter is being 'reversed' as a result>>
I spend hours reading through your site, and enjoy reading responses the team makes.
<<As do I!>>
I do need a little guidance at this point.
<<Happy to proffer my opinions>>
I currently have a 75g tank that is not pre-drilled. After a power outage, and a lost siphon I decided investing in a pre-drilled tank was ideal, and since I'm already buying another tank...might as well make it a little bigger.
I am going with a 90 since it will fit on the same stand I spent hours building. My system is 8 months old now.
To the point:
In tank I have
1 - Yellow headed Goby
1 - Lawnmower Blenny
3 - Yellow Tailed Damsels
2 - Percs
1 - Yellow tang
1 - Pink fish my wife picked up, can't remember name at the moment (at work).
<<Hmm'¦an Anthiine species perhaps?>>>
This is the extent of my fish stocking, and I've told the wife we are done adding more fish.
<<Okay (guess we'll see how that works out [grin])>>
I do have some various clean-up crew, crab, snails, corals, and shrimp, oh my! My questions all require clarification, so I'll bold the actual question:
1. I want to have a DSB in the 90 system. I currently have one in the DT part of my 75, but am not happy with how difficult it is to perform maintenance.
<<'¦? In my experience and opinion, a properly set up DSB in an adequately configured system requires little, if indeed 'any,' maintenance>>
I have 130lbs of LR in there as well, so cleaning under rock, and providing enough flow without creating ravines in the sand is proving difficult.
<<Do look up/research 'gyre flow' for aquarium systems'¦a good way to go even if you 'don't' utilize a DSB>>
I believe I have enough room under my stand for a 55g,
so I was thinking of buying one and putting a DSB there.
I realize there is no mathematical formula for size of this, but can you recommend how big I would need to have the DSB in the 55 to provide adequate benefit to the entire system?
<<A 'minimum' of 6' of sugar-fine Aragonite'¦ My own 55g vegetable refugium has a 8'- 9' sugar-fine DSB>>
Looking for surface area, and depth. Keep in mind this 55 will serve as a holding spot for skimmer, heater, etc.
<<Mmm, okay then'¦I suggest you partition off what room you think you will need for the equipment, and fill the remaining with 8' of the sugar-fine Aragonite. Adjust the height of the partition such that it will hold the sand (and maybe some macroalgae?), but is still low enough to allow water entering the refugium-side to spill over in to the equipment compartment (sump-side). Do let me know if you need further clarification here>>
1a. If putting the DSB in the 55 is fine, I was thinking of putting <1" of aragonite (larger sized for easier cleaning) in the DT for aesthetic purposes only. Is this fine or should I stick with the finer sand in the DT as well?
<<A sub-1' layer in the display of a larger grain size will be fine. I prefer a DSB in my display, but do recognize how limiting this is in smallish systems (mine is a 96'x30'x30' display)>>
2. When I transfer to the 90, I am not intending on moving the sand from the 75 to the 90, but instead was looking to buy new sand for the DSB. My 75 has a 29g with a DSB in it currently (about 30lbs). Can I put the sand I have in the 29 on top of the new DSB in the 55?
<<You can'¦this will provide a good 'seeding' for the new DSB, and do expect 'some' die-off (cycling) of bacteria at the least from the inevitable mixing of the substrate>>
3. I currently have a fluorescent light fixture over the 75 (2 12,000k and 2 actinic for 216w),
<<Too much 'blue' in my opinion>>
and a simple 100w grow lamp over the sump. The DT just got over a hair algae battle, and rock has a little, not much, coralline growth on it. The lights on the DT run 12 hours. The Sump has a grow lamp on 24hrs,
<<For what reason I wonder'¦you make no mention of macroalgae>>
and the rocks I have in there are covered in beautiful growth. Is the difference because of inadequate lighting in the DT?
<<Likely due to both a difference in spectrum and intensity>>
I am planning to go MH with the 90, but wanted to confirm this was my problem.
<<Likely so'¦though there are differing species of coralline algae with differing lighting preferences>>
I realize time is a weapon with these systems,
but if the sump can grow it, the DT should be capable as well, correct?
<<Under 'like' environmental conditions'¦correct>>
3a. Just wanted a little clarification on lighting with MH. I was planning on converting my current fixture into 4 actinic, and adding 2 250W 15,000k, or 20,000k MH lights.
<<Do what you like, but this is way more blue light than you need'¦and is not optimum re the needs of your corals unless you plan a deep-water biotope>>
Does this seem a reasonable approach?
<<Is the current 'rage' re reef lighting it seems'¦but I am a proponent for more natural-spectrum lighting. Keep the actinic fluorescents if you wish, but were this mine, I would go with a good 10K MH halide bulb over the higher spectrum (and lower output) bulbs>>
This to be a full blown reef tank.
<<I take that to mean the ubiquitous 'reef-garden' then'¦all the more reason for some 'full spectrum' MH lighting'¦in my humble opinion>>
Sorry for the bombardment of questions,
<<Not a problem>>
but wanted to come to the source, as a lot of information on the web is conflicting, and inaccurate.
<<This is true'¦but still best to gather information from several sources, and then use your own good judgment to make a decision>>
Again, your team is appreciated, and I hope you (whoever responds to this) truly enjoys this fantastic service you provide to the SW community.
<<We (and I!) surely do that. Cheers my friend'¦ Eric Russell>>

Re: Sand Bed Question (Placement, Depth'¦Lighting Too!) -- 05/23/10
Hi Eric,
Thank you for the reply.
<<Quite welcome>>
Just to clarify...
I did not have measurements for under the stand correct in my minds eye while writing this at work.
So the biggest I can go is the current 29g under the stand.
That said, I'll be going DSB in the DT after all.
<<I see>>
I'll look into the 'gyre flow' you recommended.
<<Indeed do so'¦will prove beneficial to your DSB, corals, et al>>
On the MH, you're suggesting 10,000k only, no actinic?
<<Is one option (my own display currently has 10K MH lighting 'only'), but many folks don't like this 'natural appearance' of their systems claiming the Actinics make things more colorful. But I say'¦ If you've been running 'heavy' on the blue end of the spectrum (whether MH, Fluorescent, or a combination thereof), give your corals some time to adapt to the spectral difference and higher output of the lower Kelvin bulbs and you might be surprised at what develops>>
If so that would actually be easier to set up.
<<Indeed'¦and save a bit of cash too>>
Thanks for your help!!!
<<Happy to share'¦ EricR>>

Improving Nano tank sump/DSB   2/26/10
Hello Crew,
<Hi Stan>
I have a question about "fixing" the shallow sand bed in my sump, but first a brief system description...
I have a 29g display with around 40lbs of live rock and base rock, with an overflow into a 20g (long) sump. The sump has an Aqua Remora skimmer in the first chamber, then a refugium area that is about 18 inches long, with a 5-6 inch layer of (very) live rock rubble suspended on an egg crate rack over a shallow (1-2 inches) bed of live sand. Water flows over this area, and the live rock rubble is covered with tunicates <Nice!> and small feather duster-like worms. This spills over into a pump chamber housing a Marineland 3000 pump, which goes to a SCWD that I have estimated to be flowing around 450gph. Display is lit by a set of 65w PC bulbs for 11 hours a day. The sump is not lit.
<Really? Your system might benefit from this.. have you read WWM re?>
Primary inhabitants are a single purple Condy (which is large and beautiful), a few Mushrooms, one Gorgonian, a single Rock Anemone, a Green Brittle Starfish, a few Hermits and Snails, and a huge bristle worm. <No fish? Unusual>. I will not add any more livestock other than either some Peppermint Shrimp or a pair of Coral Banded Shrimp.
My question is what is the best course to take regarding the sand in the sump? I don't want to compromise the fauna on the rock there, or risk an event with the sand that's already there. I feel like the shallow depth is a time bomb of sorts, and I am leaning toward adding sand (1mm or smaller) an inch at a time, covering 50% of the bed at a time, until I get it to an acceptable depth (is 3" enough, or should I go deeper?).
<I would either remove an inch, or, better, add several inches, one inch at a time, a month at a time. To a total of not less than 4 inches, preferably 5-8>
If removing the sand altogether from the sump is best, I will go that route.
<I would not. This is a habitat for a multitude of animals>
My display is 1" or less.
Thanks for all your efforts at putting together and maintaining such a super website!
<No problem, although most of the work has been compiled by 'older' crewmembers than me!>
On a personal note, you were very helpful a while back in setting up what has been my favourite tank in my past 20 years of aquarium keeping, and it is looking very much like the Caribbean biotope I was going for.
<That's marvelous news!>
I did cave when I saw the Anemone, but have been resolute in not adding a fish to the aquarium as I feel it would be irresponsible.
<Could indeed be. I am not an expert here, but I don't think this Anemone is easily paired with Clowns, and is definitely a danger to other fishes>
I committed myself to waiting for the tank to mature, and this has made all the difference!
<Patience pays!>
The fun my family and I have watching all the tiny creatures in and around the rock has more than compensated for the lack of fish and heavy coral stocking I see in similar tanks.
<Outstanding Stan! There certainly are several different ways to 'skin a cat'>

Re: Sohal tang as main focus fish, DSB depth  -- 10/31/09
Dear Bob,
I don't know much about refugiums hence I only used 3-4" of fine sand in my.
You suggested that I use 6" so before I go ahead and add the 2 extra inches, could you
please tell me the benefits of using a 6" bed instead of a shallower one?
Thanks for all your input,
<... please learn to/use the search tool, indices on WWM. Read here:
and the linked files above. BobF>
Re: Sohal tang as main focus fish
Thanks a lot... got some reading to do.
<Heeee! Not too much!>
<And you Bill. BobF>
Re: Sohal tang as main focus fish
Dear Bob,
<Big B>
Ok, now I know why to have a 6" sand bed.... thanks.
So what do I do now? Just add 2 more inches to the existing bed? Do I just remove the live rock and
dump 2 inches of fine sand on top of the "old" sand? Do I need to stir it 1st or anything?
This refugium has been running with 3-4" of sand for a year now.... does that matter? There are tons
of pods and tiny worms all over, should I get some inverts that like to sand sniff so that the sand is stirred?
<Add it, no need to move LR, no, not necessarily, welcome. BobF>

20gal Nano Reef/DSB 3/23/09
Good day WWM Crew,
<Hello Adriel.>
I have a question regarding DSB's. The only livestock I have now is a brittle star and a yellow tail damsel. Nitrates are at 10ppm. My 20gal "wannabe" reef has 1 inch think aragonite fine sand for a substrate with some growth of worms etc. Would like to try a DSB, and as per my reading, would require it to be 3" or greater?
<Yes, 3" minimum, four is even better for NNR in my opinion.>
My question is could I just remove the LR and the star and then literally pour the sand over the existing bed over the course of a day, given that I don't have too much livestock (would also keep the protein skimmer on at this time)? I'd hate to disrupt the existing bed and lose any existing critters.
<Well you certainly could just pour all the new sand in, but if you have a well established sand bed you may be better served to just add say a 1/4" to 1/2" at a time, over a period of several days to a week.>
Any help would be really appreciated, keep up the good work!
Adriel Rebello
<Thank you and you're welcome, Scott V.>  

Re: 20gal Nano Reef/DSB 3/24/09
Hello WWM Crew/ Scott V,
<Hello Adriel.>
Sorry to bother you guys again, just having panic attacks right now!
<OK, stay calm.>
Was wondering, how does a DSB turn bad? Is it due to a lack of sand sifters?
<Not really, generally a DSB is stirred up on a small level, not the large sandsifter types most tend to add. A Nassarius snail or two would be fine.>
Too much depth?
<Nope, not having quite enough can make a DSB fail though.>
Can it become "too efficient", consuming all nitrates and then resulting in an excessive production of anaerobic bacteria?
I do plan on stirring the top level of the sand a bit, and adding more after a year as recommended. Would a max of a 5" inch thick live sand bed in a nano-reef be overkill?
<Not really.>
In the event that the DSB goes bad, is it possible to salvage the sand and use it in a FO setup? (By salvaging, I mean by curing and adding it in small amounts to the FO tank).
<Oh yes, the sand can always be rinsed and reused.>
I'm sorry for asking so many questions, but the sand is quite expensive and I'd hate to waste anything.
<Well do see http://www.wetwebmedia.com/dsbdangers.htm for the dangers and causes...there is not much to worry about though.>
Thanks a lot!!!
Adriel Rebello
<Welcome, Scott V.>

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

Sand Bed, Deep vs. Sallow 2/8/08 Hey WWM People, Happy New Year! <Hello> Just purchased Calfo's "Coral P." book and have Fenner's "Proper Husbandry..." as well as "Reef Invertebrates", among others:) Love this Hobby and your site! <Are great books.> This 'Sand Bed' research is conflicting (Killing me), even amongst yourselves it seems:). <Is sort of a hot topic in the hobby.> 1 in, 1/2 to 3/4 in, 3 in, 4-6 in DSB. ...If I may ask, would you answer each of these questions (so that I, and others, won't waste your time asking for more specifics on the same topic with numerous emails)? Carpal Tunnel isn't fun! ...Yes, I read everything on your site. I have lost my social life. That's how much I read! Heee Heee:) No kidding. My wife's getting bored! <Ha> Questions at the end - kind of :) 1. 1 in. ( 20% crushed coral, 80% fine Arag.) is what I have as substrate. (No sump. Only - 50 gln tank, 192 watts actinic/daylight pwr compact, hang on skimmer, Eheim Can. filter, 2 HFlow power heads - 865 gln hr. each, 65 lbs live rock, airstone, 6 small fish, 2 turbo snails, two Emerald Crabs, 1 green Serpent Star, <Careful, is predatory and a known fish eater.> and a few Polyp Colonies. Sump and refugium not an option at this point. Tank is a year old (upgraded for a 24 gallon). 6 gln water changes - weekly. PH 8.2, 0 ammonia/nitrites, 20 - 40 ppm nitrates, '17KH' - a bit high (something 'in the tank' producing this - salt/water mix reads only 10KH. Could be nitrates. What do you think? How can I make this better, it seems okay at this point? 'Money and space' is an issue with the Wife:) <Always is. Have you tested your source water for nitrates? Have you cut down on feeding? Is your skimmer producing well? If so and you still have a nitrate issue then going with a DSB may help.> 2. Would a 2 in. substrate be at least better than 1 in.? <Nope> At least a little? What's the difference? It's almost three. Has to be better than 1 in, right? More sand, more beneficial bacteria, seems logical to me. But, what do I know? <Would get more ammonia and nitrite reducing bacteria, but you don't need more of these. Nitrate reducing bacteria, which is what you are looking for, only can survive in low oxygen areas of a DSB which will not occur at only 2 inches. So all you get with 2 inches is more space for stuff to get caught and decay, with the areas of nitrate reduction which counter this problem. So a minimum of 3 inches, 4+ is better, is necessary to create a hospitable habitat for the nitrate reducing bacteria.> 3. Vacuuming the sand - I see what looks like new, almost microscopic, translucent shrimp bouncing around the substrate, would rather not vacuum these little things up. Couldn't I lightly sift the sand and only vacuum the water from the very top of the tank? These types of little organisms are what I've been praying for? <Could> 4. Will the "poop" I see gathering at the bottom corners, where there is little water flow (from my Dwarf Fuzzy Lion :)), eventually be consumed by the "good" bacteria? Can I just move it into the water column without vacuuming the sand? Can I not just leave the sand be, but for a little stirring every couple of weeks? Two inches of substrate must be of some worth? <Need to improve your water flow, any time detritus is just collecting your nitrates are going to become a problem. The idea here is to keep as much organic material as possible in the water column so that it can be removed by the skimmer prior to it decaying.> 5. If I do, cause you convinced me, go 3 in. of sand, can I pour "live sand" over the top of what's already there? Should I just move all the old to one side and put the new on the other? <Can just pour it over slowly, 1/2 every few days which gives the little critters a chance to get back to the surface and not suffocate under an extra few inches of sand.> Love you guys, Ringo Gene <Chris>

Re: Sand For A Reef Aquarium 12/6/07 Thanks. <You're welcome.> For some reason I thought you needed 5-6" deep sand bed for proper de-nitrification. Perhaps we are talking about the sump/refugium. <Some folks do, I don't like using that much depth. If there should be a die-off in beneficial sand critters including fish, that deep a sand bed could turn into a nitrogen factory. I have a 2 1/2 to 3 inch bed with a very large colony of amphipods who only appear at night, and one Sand Sifting Starfish in a 60" x 18" tank. Been running about a half year now and my sand is darn near as white as when I added it. James (Salty Dog)> Best Bryan Heitman

Re: Sand For A Reef Aquarium 12/6/07 Out of curiosity why only 2.5" depth? From reading the substrate FAQ it discusses fine sand dissolving over the course of a couple years, and adding sand to an existing system will probably prove very difficult, why not start with say 3 to 5"? <Did mention why (my opinion) in a previous email to you. James (Salty Dog)> Bryan Heitman

Using both Deep and Shallow Sand Beds In Same Tank  9/27/07 Afternoon, <Hello> I have read through the benefits of deep sand beds and am starting to see some criticism of deep sand beds as well. I have a 90 gallon saltwater tank that I've had the overflow glass lowered to accommodate the waves from a Tunze Wavebox. My 90 gallon tank now holds about 78gallons + 20 gallons of water in sump. Previously, before the modification to the overflow, the tank was a full 90 gallons of water with little room at the top. During this period I had about a 3.5" - 4" sandbed and the basic water parameters were ALWAYS perfect (no signs of ammonia, nitrate, nitrite, and pH of 8.2). So why am I changing it up now after my overflow has been adjusted??? I dunno, why not... hehe. So the tank modification is done and I want to start getting into corals, clams, etc. I'm considering 1" of sand on the left side of my tank. In the middle of the tank I have built up a live rock retaining wall which supports the 4.5" of sand on the right side of my tank. The tank is a standard 90gallon at 48" long x 18" deep and 24" tall. I am curious if there is any harm in incorporating both a half shallow and half deep sandbed??<This will not have an adverse affect on nutrient reduction and is more aesthetic than anything. The sand in the sump and the sand in the tank will continue to denitrify thru bacterial activity> Of note, I also have 2" of miracle mud in the sump refugium with some Chaeto. <Make sure to harvest the Chaeto regularly so as to export nutrients.> I've had my Tunze Wavebox up and running for 10 days now. I think I went overkill on lowering my tank overflow as I still have a good 3"+ of room at the wave peak. Oh well, easier to build it up then cut it down... and perhaps I am getting more peace of mind with a smaller volume of water thus causing less water pressure referencing Tunze's disclaimer on tank blowouts. So here is my other question. I am using a QuietOne 4400HH (I think that's the model) and the calculation was circulates total system volume 6 times an hour. The Wavebox produces near total water movement throughout the tank. I'm noticing every little bit of beneficial green algae swaying with the water movement. Tunze mentions not to have circulating devices compete against the wave... thus I am not using any powerheads. Should the WaveBox alone along with water flow from my return pump be sufficient in my tank? I'm finally using the WaveBox for this tank to get the total water flow to assist in preventing the growth of cyano on my sand. Furthermore, I also am now using RO/DI water over the past month. Total water flow, filtered water, 20% monthly water changes, attentive feeding... I should be mostly nuisance algae free?? <The addition of RO/DI water is a definite benefit to the systems maintenance. Monitor it's efficiency with a TDS (Total Dissolved Solids) Meter. The reading you want is less than 2ppm. The wave box and the return pump should do a great job of circulating the water.> Hmm, how come I always have a simple question that turns into a short novel? Sorry guys/gals.<Dunno?> An observation in my 200gallon setup with a 5" DSB. During the first 3 months of tank life, I had brown/green hair algae and some cyano on the sand and rocks. My water circulation in this tank was about 18x/hour and the tank temperature averaged 27oc. At around 4 months, the tank cleared up and I had very little algae growing on the glass (I'd have to clean it once every 5-6 weeks). I had nice pure beige sand and the Tonga live rock started getting some really awesome encrusting algae colors all over it. This lasted for 4 months. Over the past two months, I've had some cyano on my rocks and incredible green hair algae growing everywhere in addition to some reddish brown patches on the sand thus reminding me of when I first setup the tank. The timing is consistent with when I installed a/c in my aquarium room which lowered my tank temperature to 24.8oc. At the same time, I have noticed our tapwater has a weird taste. Maybe the algae is water quality related or temperature related or both??? In any event, I finally go out and purchase Kent's top of the line RO/DI unit. I've only changed out about 35gallons of water and have been using 1.5gallon top-offs daily. The cyano is retreating/disappearing but the hair algae is still awful. Do you figure it would reasonably take another 2 - 3 months to see the results of my filtered water? <Yes, it will take time to reduce the levels thru dilution methods. You can use a iron based resin to remove phosphates. This will help. Even if you test zero for phosphates now, the resin will still help remove any non-detectable traces and other DOC's (Dissolved Organic Compounds). High temps will increase algal activity and stress corals. Lower temps will increase oxygen levels and promote coral growth. (within normal reef temps, of course.) I always suspect any source water that has not been reduced to 0ppm TDS via filtration.-Rich aka Mr. Firemouth> David Brynlund

DSB... Depth 25 or 6 to 4? Go With 6... Hello, <Hi there, Mich here.> I am in the process of setting up a 125 gal FOWLR. <Congratulations.> I am employing a DSB and had a couple of questions. Would a four-inch bed be sufficient or would it be beneficial to go with a six-inch bed? <If it were me/mine I would do the 6-inch bed... over time the aragonite dissolves.> My second question concerns the brand of sand to use. Would you recommend CaribSea sand which from some of the larger pets supply retailers? <Again if it were me/mine I would use an aragonite sand the likes of Oldcastle formerly South Down, though the last I heard this Oldcastle sand was getting hard to find in the USA.> Thank you <Welcome! Mich>

Hydrogen sulfide  4/21/07 I am sorry to bother you guys again.  I have been reading thru your FAQ's but am still quite (even more so now) confused about substrates.  I do not want a DSB.  I have some special grade reef sand that I recently added to my tank after my live rock cured, about 3" deep.   <Mmm, I'd increase this depth... about another inch> I have my live rock on a PVC frame and needed this much to cover it up.   Is this too deep?   <Mmm, no... but is in-between "good levels"> I recently noticed some dark spots underneath my tank and definitely smell HS gas.  Would increasing the flow around those areas help with it?   <Maybe... not necessarily H2S...> My tank was doing fine until I added the substrate it seems.  My ammonia, nitrite and nitrate levels were all at 0 for over a week, so I added the substrate.  Today I checked the levels and ammonia was at 0.20, nitrite and nitrate 0.  I am doing twice weekly 30% water changes until the tank stabilizes again.  I just don't know what is causing the spike, I am worried it has something to do with my substrate.  I have 6 hermit crabs and 8 snails, which were added after the rock cured. Also, is it normal for brown algae to grow on the live rock like it is now?   <Yes...> I hear stories about how people have cool stuff growing on there live rock, I haven't seen anything on mine yet and it's almost been a month. Shanna <Please read here: http://wetwebmedia.com/marine/setup/index.htm scroll down to the brown line... on DSBs... Bob Fenner>

Deep/Shallow Sandbed...In One System!  -- 04/11/07 Morning all, <Hi there! Scott F. with you!> So I realize that some people prefer shallow sandbeds or no sandbeds... and some people prefer the deep sand beds. <Yup. Ask 20 different reefkeepers and you'll get 20 different answers!>   Is there any harm of having both?  For instance, if I  start with a 1inch sandbed completely across the bottom of my tank and then use live rock to build somewhat of a dam like structure thus splitting the tank bottom in half.  If I then top up one side of the liverock dam with an additional 2-3" of sand and then finish aquascaping with the rest of my liverock, I'd have the left side of my tank with a deep sandbed, and the right side of my tank with a shallow sandbed. <Interesting. In fact, I am working on an aquascape very similar aquascape concept in a large tank. In essence, you're "terracing", just like you see in freshwater planted systems. It can be a nice look, and provide interesting benefits. You could even keep it really simple and just slope the sandbed from front to back or side to side. Arguments can be made that detritus accumulation can occur in such a sand bed, but I feel that this can be very successfully maintained with good husbandry techniques, good circulation, etc. Use of detritivorous animals and careful maintenance can make a difference, as well.> I have read a few hobbyists complain that a deep sandbed will eventually not be able to absorb nutrients, thus eventually providing no benefit??? <Well, you'll hear hobbyists assert that their sandbeds are "saturated" with nutrients, and claims that phosphates and organics are leaching back into the water. This may or may not be factual. On the other hand, it is widely acknowledged that the micro and macrofauna in sandbeds can wane over time, requiring an occasional "re-charge" of beneficial creatures. There are lots of other factors that can affect the function of deep sand beds; I encourage you to read more on the WWM site and elsewhere for details. Authors such as Ron Shimek and Bob Goemans have written extensively on deep sand beds.>   Anyhow, I currently have a deep sand bed and have been suffering from Cyano mostly on just the sand... hopefully my Tunze Wavebox will take care of this once I install it. <Additional water motion/circulation can provide many benefits!> I wanted the deep sand bed portion for a Yellowheaded Jawfish. Does the plan sound ok?  Can you see any biological faults to my plan? <To be honest with you, I'd go for it. I think that experimentation, once you've armed yourself with some background, is what makes this hobby so interesting. Good luck to you! Regards, Scott F.> David Brynlund

Shallow or Deep Sand Bed? - 2/21/07 Thank you so much for the quick response Justin!   <No problem, my friend... glad to help!> I didn't expect to hear back from anyone for a while.   <We try to respond to all within 24 to 48 hours, otherwise we get backlogged ourselves!> I'm sure you have TONS of emails coming in daily.    <Oh, yes> I had another question that I haven't been able to find an answer for.   I'm not sure if I should go with a 1/2" shallow sand bed, or a deep sand bed....which has to be what...3" or more? <Yes, a minimum of 3 inches is needed, with 4 inches likely to be a better solution.> Something in the 1"=2" is a bad idea correct?   I'm only going to have a 54g corner tank, so I don't want to lose too much water volume by having a 5 or 6" sandbed.  What are the pro's and cons of both? <In the display, I would go for a 1/2" to 1" layer of sand, for aesthetic purposes. As far as the deep sandbed goes, while they are a wonderful denitrifier, if you plan your new setup accordingly, this won't be necessary. Plan to use your sump as an algae refugium and/or include some live rock rubble in it, and you'll be good to go!> If I go with a 1/2" sandbed, is it better to get the sugar fine, oolite, something courser?   <Oolitic sand is always my recommendation here... the more coarse materials have risks of sharp edges and waste accumulation. Easier to just avoid such issues, IMO.> Thanks! Pam <No problem, Pam. Glad to be of assistance! -JustinN>

Nuisance Algae/Substrate Depth - 01/23/07 Hello, <<Howdy>> I currently have a 75g reef tank with a 20g refugium. <<Neat>> I have been battling hair algae for months.  I scrub it off in a bucket and it grows back in a month. <<Mmm, as you're likely aware this is generally associated with nutrient control...have you read here?   http://www.wetwebmedia.com/nutrientcontrol.htm  >> My phosphates are near zero and nitrate around 10ppm. <<I would guess the phosphate to be the problem here.  Unless the tests are inaccurate, the abundance of algae in the tank should be utilizing the phosphate before the hobbyist test kits can get a reading...unless there is a gross influx coming from somewhere.  Obviously the best option is to find/eliminate the source of excess phosphate, but in the meantime you should consider employing a chemical phosphate binder (an iron-based GFO and/or Poly-Filter)>> I have 3-inches of sand in the refugium and 1-inch of sand in the display tank.  My question is should I add more sand to the refugium and only have around one half-inch of sand in the display? <<You can do this, yes.  It will likely help with nitrate more than phosphate, though reducing the depth of the bed in the display may reduce trapped/decaying organic matter thus indirectly contributing to lower phosphate levels>> I don't really want a 6" DSB in the display but I don't want to see the glass either. <<Understood...it is fine to put the DSB in the refugium and leave a shallow bed in the display for aesthetic purposes>> The circulation is well balanced and the hair algae grows no matter what I do. <<Try to determine the source of the nutrients.  Elevating/keeping pH in the 8.4-8.6 range has anecdotally been shown to help limit algae growth...as has increased alkalinity.  Aggressive skimming will also help (you don't mention a skimmer) by removing organics from the system before they can break down in to the elements that feed the algae (nitrate, phosphate, etc.)>> I've siphoned water from underneath the display tank sand and it comes out brown.  Is it ok to have a DSB in the refugium and a shallow layer of sand in the display? <<Absolutely yes>> Any help would be appreciated. <<Do read through our articles/FAQs re nuisance algae, starting with and continuing from the link I've provided>> Thanks, Michael <<Regards, EricR>>

DSB For A Large Tank - 04/09/06 Dear Bob, <<EricR here this morning...I think Bob is still asleep/recovering from his Lavaman ordeal <grin>.>> I currently have an 8ft tank and would like to add a deep sand bed to assist in denitrification and to provide more comfort for my stingray. <<A very good idea in my opinion.  I too have a 8ft tank, with a 6" DSB...but no stingray (is a reef display).>> I have read the article on the website, and am aware that 3" depth is a minimum. <<Mmm...can depend on 'grain-size' of the substrate, with larger grain-sizes meaning deeper beds.  But even when using sugar-fine sand my preference is for a 4-inch minimum.>> There is 40kg of fine coral sand, 12 kg of fine grade aragonite currently in the tank which makes up an average depth of between 1-2 inches.  I will create the DSB by adding sugar fine sand, although I would like your opinion as to how deep I should go? <<Were it me, with this mix of sand, I would shoot for an absolute minimum depth of 4 inches...even 5 or 6 inches if your not opposed to the look/loss of depth to the open water column. I know that bigger tanks require deeper sand beds. <<Not sure I agree with this.  All things equal, the sand bed will be proportionately larger in the larger tank.  As far as I'm concerned, 'minimum' bed depths would apply equally to all tank sizes.>> Current inhabitants included a small masked-stingray, 3 snowflakes. <<Sounds like a very nice display.  This ray (Dasyatis kuhlii) seems to be one of the better choices for aquariums (not to be confused with Taeniura lymna...another/different 'blue-spotted' ray with a very poor survival record) and will definitely appreciate a 'fine' sand bed.>> Also, I have attached a spare 10g tank as a refugium (which I know is small, but at least it puts the tank to good use) and would also like to know if creating a deep sand bed in there, without having a DSB in the main display, would have any sort of effect on denitrification? <<Probably not a noticeable effect...considering the size/stock list of the display.  I think putting the DSB in the display is your best option.>> I'm just trying to get my head around the proportionate area of DSB and its correlation to the degree of denitrification. <<Please have a look here:   http://www.wetwebmedia.com/deepsandbeds.htm >> Thanks in advance, Joe <<Quite welcome.  Regards, EricR>>

DSB Size/Depth - 08/29/06 Hi again, <<Hello>> I am trying to add a DSB for my 125 FOWLR due to a persistent nitrate problem. <<Ok>> I do have sand in the main display at present but due to the home improvements done by my fish on a regular basis the SB is 2-3" in some spots and much less in most others. (Apparently they don't understand the benefits and keep moving it around when I try to fix it.) <<Ha!...indeed>> Be that as it may, how big of a sump/refugium and how deep of a SB would be an appropriate remote DSB? <<In my opinion...As large a vessel as you can practically employ, with a "minimum" 6-inches of sugar-fine aragonite>> I also have close to 200lbs of LR in the system.  Thanks again for all your help. Mordy <<Regards, EricR>>

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  >>

- 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 -- >

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.>

Deep Sand Bed Height - 1/26/04 Hello there, <Hi> I am constructing a 15 gallon sump for my 29 Tall aquarium. The sump will have three compartments, the first will be for the run-off / skimmer, the second will be a 10" Wide x 12" Deep (or 120 Square Inch) live sand area, and the third will be for the return pump. I have heard that 6" was a good depth for a DSB. <Yeah, but not exactly the rule of thumb> Can you tell me what you recommend for my set-up.<4-6 inches is fine. Be sure to add some quality live sand from some other aquarist's tank or from a trusted LFS. The bag stuff just wont quite do it. Not that it is not a good product, but not as full of various inverts that are beneficial to the sand bed> If I didn't have to go 6" deep, instead using a 4 to even 5" deep DSB, that would help my design much better. <Then go for it. No worries. I think you will find the benefits somewhat the same. Quality over quantity> I want to make sure that I will get the same benefits from a 6" DSB though. <You will be fine. Happy reefing! ~Paul> Thanks a bunch! Aaron

Deep Enough Sand Bed? Hi guys, <Scott F. your guy tonight!> after going through all your DSB pages, I've decided that I'm going to add one in to my established 4ft tank. I am currently half way through my project, and have hit a bit of a snag which i hope you guys could help me with. <We'll try!> I've also bought a refugium, which I'm adding to the system as well. Originally, I was only going to the DSB in the refugium, but decided to put it in the tank, because I knew that I would always be regretting it. So, I get home after buying all the very fine sugar-size sand I could get (I've found only one place that gets it, and I bought it all), put all the fish in the shiny new refugium, took out my old gravel, and put in the sand. The problem is that I only have enough sand for about 3.5inchs deep, and can't get any more for at least a month. My understanding is that this is not deep enough. <Well, it's not a "deep" sand bed at this depth- but it is workable> I'm not really sure what to do, but I see the below as my options: 1. Leave it as is (with 3.5 inches). I remember seeing that cos its finer, doesn't need to be as deep, but not sure of the minimum. <Well, there are many thoughts on this. As I mentioned above, it can be useable. You can always add some additional depth as you locate the substrate> 2a. Add some more sand that would be larger grained, about 1-2mm, and mix it in with the sand. <Can be done, too> 2b. Put an inch or so of the coarser sand OVER the fine sand. <A possible solution> 2c. Put an inch UNDER the fine sand. This will be a bit trying tricky, and will cause another sand storm. <I wouldn't do this> 3. Use all the fine sand to make a 6-8inch DSB in the refugium. Main tank  has a foot print of 48x14, refugium would have a DSB of 23x12. <A viable option...> 4.Wait a month for more sand to come in. <That would be my call> What would recommend? <I'd go with #4, myself> Also, does the sandstorm affect the fish? <Could irritate some fish or inverts, but I wouldn't be overly concerned if you're careful> Thanks in advance. My system is currently pulled apart, and I'm sort of in panicky mode, because I don't know what to do... <Don't panic...You'll be fine leaving things as they are for a while. Just obey the common sense rules of husbandry, and you'll be fine! Regards, Scott F.>

Deep Enough Sand Bed? (Cont'd.) Hi Scott F., thank you for your response, but i have a follow up. <Ask away...> I was in a rush (i.e., my tank was pulled apart), and decided to go ahead option 2c below, where I now have 4-5 inch DSB, with about 2 inches of more course aragonite (1-2mm), and on top of that, 2-3inches of very fine reef sand. You said you wouldn't do this, but unfortunately, i already did. Is this something bad? Should I redo it? the sand is very fine and blows around easily, should I put another inch layer of the 1-2mm aragonite over the top, adding an additional layer? <Actually, I don't really see any harm in this. Yes, DSB "purists" will want a DSB constructed exclusively of sugar fine sand, but I personally have not had problems in mixing different grades of sand together. > I'm not sure why you don't recommend it, I thought that the finer sand was recommended for infauna growth and movement? Or was it not recommend because of the storm it would produce? <Well, I didn't recommend this because it seemed to imply that you were going to disturb the lower level of fin sand in the process. My concern was that you would seriously disrupt the very processes that you are trying to foster in a DSB. Organic material can be released into the water en masse with such a disruption...Sorry if I didn't fully explain my concerns...> Thanks. <My pleasure! Regards, Scott F>

Deep Sand Bed >Greetings from Northern California, >>Greetings from Southern California!  Marina today. >I'm currently setting up a new 18 gallon reef tank, and currently have a little over 2" aragonite substrate (.5mm-1.7mm). There is nothing in the tank right now but this, and water mixed at a SG of 1.026. Reading your articles about the benefits of natural nitrate reduction by using a sand bed at a depth of 4" or more has convinced me to try and implement this for the great long-term benefit it would provide. >>Great! >I would have gone with a really fine substrate, but have been unable to find it in my area. One of your articles mentions that at larger grain sizes, a greater depth is required. I wanted to know if I can use the grain size I mentioned above to create an effective DSB, or if I should try getting some fine aragonite through the mail and then adding that along with the existing substrate. >>Your biggest limitation is the tank space you'll lose going deeper, but it most certainly can be done.  I would suggest 5"-6". >In either case, I would like to know the depths I should be aiming for. >>DSB's seem to work best when they're at least 4", although you'll find/meet many who go as shallow as 3".  The whole point is to create a sufficient anoxic area, and because the tank is almost considered a nano, you'll have to make up partially the surface area with depth.  I think you can achieve admirable results using what you have at a depth of 5"-6" (doesn't have to *all* be that depth), Brian.  I do hope this helps, and best of luck!  Marina

DSB Questions Mr. Fenner, <Hi there> I am contacting you in regards to DSBs.  I have a small reef website, mainly informational, with the intent to promote tank raised frags, tank raised fish and aquacultured LR.  I have also developed an interest in helping beginners avoid those mistakes we all make as newbies... <Or "oldbies" for that matter> I have a free newsletter I send out, and am thinking about doing an article on DSBs, and I would like comments from some of the experts...  So if you wouldn't mind, would you please take just a moment to answer the following question: "What would you consider to be the one most important factor in starting, and/or maintaining, an effective DSB?" <... just one? Okay, the depth of the material used... though (of course it's make-up, particulate size, uniformity... are important as well. But in my estimation, more folks "fail" with their DSB's due to a lack of depth of substrate than any other single factor> If you have the time, I would love to have any comments you have about my site.  Please feel free to stop by. <Oh, yes. We have a link to your site. Good show. Bob Fenner> http://www.fragexchange.com John McCann FRAGexchange.com

Substrate depth Hi guys, oops.. and gals :)  <howdy> Just wanted to thank you for all the help you have been able to provide it the past. The things you all do for the hobby are immeasurable. I was planning on a DSB of 4-5" in my 75G reef tank with CaribSea Aragamax (1-1.7mm size), but let me know if there is something better. And if I used a smaller grain size could I make a shallower bed and still be able to achieve an anaerobic area to reduce nitrates? Or would this not be recommended?  Thanks once again for all your help and knowledge.  <This is a fine sand to use.  Your sand bed should be at least 3.5' but 4-5 would be better.  As for the smaller grain, I would stick with the Aragamax because anything too much smaller would just be mud. Cody> Best Regards, Jeremy

Deep Sand Bed and Aiptasia control Hello, <Hi Rodrigo, Don here today> I have no words to appreciate all the benefits everyone can get here in your web site. Thanks a lot. <Thank you, it is an honor for me to be a small part of this> I have very high nitrates (huge)  in my reef tank. Everything looks fine with the fish and corals but reading here I just notice that my sand bed is in the range where you say is not good (1" to 2"). My tank is 29gal (the base 30" x 12"). I am planning to increase the deep to 3" or 4" using the Southdown Sand. Is this sounds good? <I would go 4+ while you are at it.> I am planning to do a 50% water change this weekend that I haven't done since 6 months ago. <Yes, likely a major part of the problem. If you can, changing 3-4 gallons weekly will do wonders with the water quality> May I ask you how to mix the new sand with the existing one? I thinks some of the actual sand is fine but also some it is not that fine (not coarse either). Or should I put the new sand over the old sand? Maybe I should do the opposite? Right now I have a couple of Maroon Clown fishes and a bicolor Pseudochromis so I think these guys are hardy enough to resist some chemistry changes. I also have skimmer, AquaClear with Polyfilter and Chemipure. <If the existing sand is < 2mm then I think I would go right over the top, a little at a time.> I have a second question: I have some Aiptasia, like 10 of them. One month ago I tried to introduce a peppermint shrimp but the Pseudochromis bicolor bothered him until he died. Should I remove the bicolor from the tank? The Aiptasia looks very ugly. <Check here for more info on controlling Aiptasia: http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/aiptasia/aiptasia.htm Hope this helps, Don> Thank you very much, Rodrigo.

Depth of DSB 7/7/03 First, Anthony and Bob; I'm enjoying your new book. A lot of very interesting reading. Anthony, thanks for the inscription. <very welcome my friend... thank you :)> In it you bring up that 3 inches of sugar size sand is the min. for NNR. Do you have any studies that back that up? Want to know for when I am talking to people about their tanks. <Dr Rob Toonen has released some prelim data on such matters... will have full report soon I hear. Other data exists (some of the original work) from French academic aquarists in France dating back to the late 1980's/early 1990's (Jaubert, Ounais). To be honest though... I'm really speaking from a decade of practical experience. I used 48,000 lbs of the sugar fine aragonite sand for my mariculture facility. Heehee... this combined with similar reports from colleagues led me/us to the statements> The other question is about the "half-life" of 18 to 24 months you bring up on page 36. I've not seen that in any of my tanks with aragonite DSBs. <indeed... 'tis because of the commonly variable pH that works in the favor of aquarists in this case (not dissolving the sand consistently/fast enough... but at the expense of dissolved bio-minerals)> I have a number of tanks with 3 or more inches of aragonite that are 2 to 3 years old and do not seem to show that in any of them. <without a Ca reactor, such tanks usually do not have fast coral growth either (scleractinians). No worries at any rate> Could this be caused by having too many borrowing detritivores or animals like pistol shrimp? Thanks, Ray Pollett <no my friend... really just a matter of adequate water flow and various faculties to dissolve the material. A matter of grain size too if larger. Kind regards, Anthony>

DSB 29 gallon I am planning on converting my 29 gallon FOWLR aquarium to a reef type aquarium. I would like to replace my current crushed coral substrate to a sand bed. I am considering a DSB, however I cannot decide whether this is practical for this size tank. If it is practical, what depth would you recommend? <DSB stands for Deep Sand Bed, with the deep being the operative word here. Four inches or more is our standard recommendation.> Thanks, Mike <You are welcome. -Steven Pro>

DSB for a 29 gallon: How many bags of sugar-sized sand? Thanks for the quick reply.  I decided to use CaribSea Aragamax Sugar-Sized Sand. <That's what I have in my tank.> It comes in 30 lbs bags.  About how many bags will I need to obtain a 4 inch depth in a 29 gallon?   <It's hard to say. Visually compare the size of the filled sand bag to the overall size of your tank and make a guesstimate. If I were you, I would buy two bags and tell the shop owner you may need to bring one back unused. Most LFS are pretty god about these things as long as there is a clear understanding up-front.> Thanks again.  Mike <You're welcome! David D.>

Debate... (Deep Sand Beds...) Hi Bob... Thought I'd get your opinion on something that seems to be of some debate on the http://wwwsaltwaterfish.com message board. <Okay> The deep sand bed. How deep?  <A few to several inches in most hobbyist set-ups... depending on grade, composition/make up, how spherical, desire of use... chemical, habitat...> Sand sifters or no sand sifters?  <I say with in most cases> The debate is about the bacteria that exist within the DSB that help eliminate nitrate levels. Some say that sand sifters are good and help mix things up...others say that sand sifters disturb the colonies of bacteria that need an "oxygen less" atmosphere to survive. The anti-sand sifters also claim that disturbing the DSB might release toxins into the tank. Do you have an "official opinion" that I could share with this group? <Yes... that all these statements are valid within degrees... most all erstwhile sand sifters only move about the upper centimeter or so of material... no big deal... and as some folks state/d of benefit as well> Also, thanks for tipping me toward the CPR site to look at their HOT refugiums. I'll be getting one of those in the next couple of months. <Good designs... the owner of the company (Suk Kim) goes to a lot of the hobby venues (WMC, MACNA...) and listens carefully to what folks are looking for, having troubles with... in designing, offering new products. Smart> Still have to put the rock in the tank...it's almost done cycling. Hopefully all levels will be 0 this weekend so I can build my reef. The empty tank is getting a little dull as far as decor in the living room :-) I've also recommend the CPR refugiums to others on the board mentioned above. Since I can't really give my own advice yet, I will have to site yours. Seems to be a hot topic. <Good to find folks thinking, debating.> As always, your advice and guidance are appreciated! Kind regards, Misty Johnson <Be chatting. Bob Fenner>

DSB & "Stuff" Greetings all, I just completed the move from New Hampshire to California....it was not an easy task. I am setting up my 48 gallon bow tank and went with a 5 inch deep sand bed (oolitic aragonite)...lord ONLY knows where the fish are going to fit with all that sand. The effective space is reduced to about 15 inches. But the nice thing is that the "bottom" is closer to eye level so viewing critters should be easier on the back. On that subject, I had an interesting experience when fly fishing last month that made me think of the DSB discussions. There had been a fire in the Sierras and the stream I was fishing was full of sediment, about 3-4 feet deep. I stepped in and sank up to my freakin' neck and (after I realized I wasn't going to die in quicksand) I notice the distinct smell of sulfur! It was bubbling up from the bottom of nature's deep sand bed, you could see it rising in bubbles all over the place. It was neat to see a live working model of something we always bandy about here.....so I guess if you go with a 4' DSB you might really have a problem in your tank <grin>. <I have seen 12" sand beds that did not produce Sulphur gas. At a certain point though, you are not really any more productive as far as denitrification or critters. I aim for 4-6" myself.> By the way, my wife still insists that the bubbles were coming from my waders. Anyway...on another note, I noticed that the house I'm in gets up to 86 degrees on REALLY hot days (only a few hot days a year in Silicon Valley luckily). There's no a/c in the house. Do you think I might need to spend a zillion dollars on a chiller? <I would much rather spend the money on AC. Even a one room unit is more cost effective and makes watching the tank more enjoyable.> Also, I'm on the hunt for some decent live rock in the south SF bay area so if anyone knows of a good retailer I'd be grateful for a referral. <Do ask for recommendations from online message boards. Ours is at http://wetwebfotos.com/talk/index.jsp> Enough rambling for now. Thanks so much for all of your help. Don't ever quit, I won't know what to do. Wes <And neither would we with all the free time. -Steven Pro>

Deep Sand Bed/No Sand Bed/Shallow Sand Bed? 7/5/05 In planning a new 90 gallon, quick question or two - Do DSBs really, truly play a significant role in nitrate reduction. <They have been proven to perform this function, if properly implemented and maintained.> Some folks seem to downplay them, at least in part pointing to their hazards (crash, etc.) and as being a detritus trap. <A possibility if poor husbandry techniques are employed. The "nutrient trap" idea is often brought up in hobbyist discussions and message boards. With good maintenance and overall husbandry techniques, the deep sand bed can be an effective ally in natural nitrate reduction for many years.> Would it be a bad idea to set up my 90 with say only a 1 inch sugar-size sandbed (more for aesthetics) so as to facilitate keeping the bottom clean in lieu of some nitrate reduction? <If you are going to use some substrate just for aesthetics, then you'd be better advised to go with 1/2", in my opinion. One inch is too shallow to foster denitrification, but possibly too deep to be fully aerobic. A sort of biological "no-man's land", if you will. In summary, it's better to go really shallow.> I'm guessing you'll always come down on the side of the DSB (but not sure)? <Well, I am truly supportive of both DSBs AND Bare bottom techniques! It really comes down to husbandry. I have maintained both with success, and many other hobbyists have as well. My current reef system is actually bare-bottomed. I elected to go with bare bottom simply because I am employing a tremendous amount of flow, which would send sand all over the place! It was not a choice I made for any other reason, really, but it is working fine. I personally do not like the aesthetic of a bare bottom, but you do get used to it after a while.  My tank chemistry and overall water parameters are great. I will probably ultimately use a very shallow (like 1/4" to 1/2") bed of medium grade substrate, just for aesthetics, in my system. I might add that I am a water change fanatic and an enthusiast of good husbandry techniques. There certainly seems to be a lot of backlash against DSBs on some of the hobby message boards of late. Granted, no one technique works for everyone all of the time. However, I am not so sure that I agree with or understand all of the things being said about bare bottom technique (like the idea of "wet skimming", which to me seems like a strange concept...Why not just do regular, old-fashioned water changes, and pull out dark skimmate regularly? I'm sure there is a well-thought-out reason for it, but I just don't quite get it.). Like any methodology employed within the hobby, there are some fine hobbyists on the cutting edge researching and sharing their findings, and their findings do warrant your attention, with the usual caveats about employing a healthy dose of skepticism. I do take some degree of offense with those who say that bare bottom or DSB is THE way to go. In my opinion, a DSB is excellent as well. If detritus is allowed to accumulate, bioload is excessive, and husbandry is not up to par, neither system will be effective. Of course, I am convinced that those hobbyists who are successful with bare bottom tanks could be just as successful with DSB driven systems. Sorry to go out on a soap borax, but I think that it needs to be stated that both concepts can work, IMO.> If I go DSB, would 6 inches of sugar-size be satisfactory to see real benefit?   <Six inches should do the trick.> Under the 1 inch sand scenario above, accompanying that plan would be a 20 gallon refugium underneath (perhaps with 6 inches of sand there) and a separate sump of about the same size for a good skimmer such as a Euroreef or AquaC 180.  With this setup under the tank, would the 1 inch sand bed in the tank be good?  Advisable?  Not so smart?   <The idea sounds fine, but I would opt for 1/2" or less in the display, myself. Either of the skimmers that you mention would be great, BTW!> Just trying to be thoughtful in my planning.  Thanks for your time. <My pleasure! Sorry for the essay, but I think that there is much on the subject that we all have to learn! Do share your findings, regardless of which way you go! Regards, Scott F.> LED Lighting, Sandbeds, Worms?, and Starfish legs 7/7/05 Hi!     Four quick questions:  1) What's the latest on LED Lighting for reef tanks?  Any major developments?  I bought an LED flashlight a year or so ago and was amazed at how much light they can put out with relatively low power consumption and seemingly little heat.  Seems ideal for our hobby. < There is no update here yet.  But Tullio is going to be talking about this at MACNA this year.  So far they are the ideal light source that isn't available. > 2) What's the latest philosophy on sand bed depth?  Last I heard, everyone was talking four to six inches.  The other day a guy at my LFS said deep beds are out ("they're fine for three or four years, then they crash.") and one inch is now the preferred depth.  < I've always been a fan of 3 inches, and still think that is the most recommended option out there. > 3) My small salt water tank has been running for about three years (oops! and it's got a three inch sand bed....see question #2!!!) and is doing great.  < Then don't worry about anything. > When I put in any kind of meaty foods such as freeze dried brine shrimp, dozens of almost clear hair-like filaments one to two inches in length come out of the live rock and sand, groping for the food.  What the heck are they?  Nobody at the LFS seems to know exactly what they are, but everyone thinks they're a good thing and indicate a healthy tank. < I agree.  Don't worry just enjoy. > 4) A second sand-sifter starfish in my tank is losing it's legs.  The first one unfortunately didn't make it.  Is something eating them? < More likely a starvation problem.  I don't recommend them in a reef tank and I think they are hurting your tank.  I wouldn't be surprised if this second specimen is suffering from the lack of food due to the first specimen. I'd either directly feed it, or remove it. > What's going on?  I have some red-leg crabs, one emerald crab, Turbos and some Nassarius.  Fish are Chromis, clown and a lawnmower blenny. Nothing aggressive. Water quality, temp, etc. is all within acceptable limits.     It's amazing how many "experts" there are at the LFSs.... but everyone has a different answer!  This website is a fantastic service.  Thank you guys so much for donating your time and your expertise to his hobby. < You are certainly welcome. > <  Blundell  > Is it deep enough? 8/14/05 Hi I would like to know if going DSB 4" to 5" in a 125 gal  reef  tank would be sufficient to bring down nitrates to acceptable levels? <Will help> I have intakes spaced 4" from the bottom and to put  a 6" bed might complicate the water flow. <Can, could likely be "tee'd up"...> The intakes also are located in the middle and at the top water levels. Also, Can I keep my orange spotted cleaner goby? <Mmm, likely so> Will he disturb the bacteria bed? <Likely not much> Are Nassarius snails good? <... yes> What can I do to keep the detritus levels down without disturbing the proper bacteria bed? Thanks for your input............. David <Please read here re:   http://www.wetwebmedia.com/deepsandbeds.htm and the linked files above... Bob Fenner>  

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