DSB - Deep Sand Bed - Experiences

[eson]

I wanted to start a new thread on DSB. Since this is a section for those new to reefs, I thought that it might be good to start thread to this very important topic.

I got this link from Bartman, from another post (tanks Bartman). It is a very good article and it should be read by all those who are considering a reef tank

http://www.rshimek.com/reef/sediment.htm

Please post your experiences and any links that may be helpful to me and others who are interested.

eson

[Pineapple House]

Basicly, Ron meantioned most of what needed to be said. I would highly recommend a DSB to anyone out there. What brings many people away from this, is the cost. Live sand can be expensive, esspecielly when setting up a 4-6 inch sand bed. The alternative would be southdown play sand, from your local Home Depot. This is a Calcium Carbonate sand, that will do good in your tank. The only problem is it is not availible in all areas, and is quite rare at times. Stay away from marble based sands, these are known for changing your pH around. Silica is okay, but I find it un natural looking. Most Calcium Carbonate sands are awesome to use.

Also, stay away from sandsifting gobies, sand sifting starfish, or any other fish/invert that will terorize the sandbed!! They will eat all your organisms living in your sand bed, that you want to get to grow.

Lastly, I would wait 4-6 months before adding any fish/corals to a DSB. Although you can get away with adding fish right after the tank has cycled, it is good to let the DSB mature a bit, and start functioning properly. The longer you wait, the better. Some people might disagree with what was said. But, this was from other peoples experience, including golfish, SPasse, and Ron Shimek himself. As well as many other people lurking around RC.

PH =)

[ssgibby]

I have to agree with Pineapple House, I would wait for several months as well. If you have a friend that has a mature bed, you could trade a cup full or so. I was lucky enough to get southdown, I have also read that crushed limestone works very well. Unfortunately, I have no real proof. Maybe someone here will know.

[Pineapple House]

I was lucky enough to get southdown, I have also read that crushed limestone works very well.
It works just fine, but usually limestone has bigger grains of sand, which can be a slight problem when you are trying to get smaller grains of sand. Of coarse, you can you it, as the bacteria and life will eventually spread throughout the bed (someday the limestone will be live, usually takes 6 months or so, another reason to wait 6 months before adding anything).

PH =)

[HoopsGuru]

It works just fine, but usually limestone has bigger grains of sand
One of the negative things I have seen about using a larger grain size what written by Shimek in which he states that the sandbed fauna requires a mixture of "sugar" sized grains and smaller some will not colonize and reproduce in larger substrates. This was part of the reason why crushed coral has lost some of its functional use, along with its tendency to trap debris and waste. Not sure if the crushed limestone is large enough to have the same issues.

[Zack]

You have got to rember that if you mix size evetully the lager size will always end upo at the top just somthin to think about :D

[HoopsGuru]

Except you are talking about a very gradual change with sugar sand and much smaller grain sizes to begin with. This is why it is not recommended to mix CC with a DSB or add it on top....it lowers the effectiveness of the DSB.

In addition, for your tank Zach, I would be interested to know a bit more about it. General consensus for a sandbed is either less than 1" or over 4". Anywhere in between and you could have trouble. 3" is considered too deep for an aerobic zone to reach, yet considered not deep enough for an anareobic zone as well. How old is your setup? I would look more into this if I were you, you could be headed for problems.

[phistio]

my DSB is only 1.5" deep, it is live argonite from carib-sea...

also, there are no dead spots in my sand bed. all of the live rock sits atop stands made from bent lexan (extruded acrylic)

if anyone would want stands, i'll send them free of charge...you just have to pay for shipping!

[Hopeful Reefer]

If anyone would want stands, i'll send them free of charge...you just have to pay for shipping!

How big are they...how much weight do they hold...and how much to ship...

[phistio]

hopeful reefer...i pm'd you with info!

[Reefer_Addickt]

how can it be a DSB when it is only 1.5 inchs. Deep Sand bed would that be more a Shallow Sand Bed

[HoopsGuru]

Agreed, with only 1.5" inches it is not a DSB but a sand bed. It is capable of nitrification but not deep enough for anerobic denitrification. Still efficient I'm sure, although if it had a dead spot I don't think you would be able to tell unless you released it by accident and saw the effects on your livestock.

[phistio]

actually i've heard of even 1/2" depth considered a DSB...while i agree my SB is not a DSB, i was using the term for ease of recognition...


as far as "dead spot"...i mean that the sand has no fixed object on top of it to inhibit the natural stirring/turnover biological process. no live rock sits directly on top of the sand in my setup...the sit on stands that are about 1/2" taller than the sand bed, and cannot be seen.

[Bob Ashcraft]

What brings many people away from this, is the cost. Live sand can be expensive, esspecielly when setting up a 4-6 inch sand bed.

Another drawback to a DSB is, they look terrible. Many people keep their tank in a living room where it's important for the tank to look nice. When algae grows between the glass and sand, it's very unsightly.

Then, there's the issue of losing all that space. When you have an 18" or 20" tall tank, and 4" to 6" of it is sand, that doesn't leave much room for anything else.


Lastly, I would wait 4-6 months before adding any fish/corals to a DSB. Although you can get away with adding fish right after the tank has cycled, it is good to let the DSB mature a bit, and start functioning properly. The longer you wait, the better. Some people might disagree with what was said. But, this was from other peoples experience, including golfish, SPasse, and Ron Shimek himself. As well as many other people lurking around RC.

PH =)

OK, so what bad things are going to happen, or what good things aren't going to happen, if fish are added too soon?

[Pineapple House]

Another drawback to a DSB is, they look terrible. Many people keep their tank in a living room where it's important for the tank to look nice. When algae grows between the glass and sand, it's very unsightly.
Of coarse, that is just your opinion. try comparing Slicia based sands with DSB, and tell us what you think. It doesn't matter too much of what you think it ugly, but rather the purpose it has. IMO, those filters and all those wires in the stand are very ugly, yet they serve a very usefull purpose.

Then, there's the issue of losing all that space. When you have an 18" or 20" tall tank, and 4" to 6" of it is sand, that doesn't leave much room for anything else.
Yes, it does take up space, can't argue with that. But, it's not the space that really matters, but what it provides for you.



OK, so what bad things are going to happen, or what good things aren't going to happen, if fish are added too soon?
Of coarse, nothing 'terible' is going to happen :wink: but it is very good to add fish and corals only to a matured DSB. Why add any sort of fish or coral to anything but a matured tank? A DSB will take 6 months to become fully functional, and matured. I would never recommend adding anything to a DSB until your tank is a minimal of 6 months old. Like I said, nothing 'awefull' will happen :roll:

PH =)

[Bob Ashcraft]

Another drawback to a DSB is, they look terrible. Many people keep their tank in a living room where it's important for the tank to look nice. When algae grows between the glass and sand, it's very unsightly.
Of coarse, that is just your opinion. try comparing Slicia based sands with DSB, and tell us what you think.

I don't understand. Why would anyone compare a silica based sandbed with a DSB?


It doesn't matter too much of what you think it ugly, but rather the purpose it has. IMO, those filters and all those wires in the stand are very ugly, yet they serve a very usefull purpose.

Yes they are, but I can close the doors on my stand so other people don't have to look at it.


Then, there's the issue of losing all that space. When you have an 18" or 20" tall tank, and 4" to 6" of it is sand, that doesn't leave much room for anything else.
Yes, it does take up space, can't argue with that. But, it's not the space that really matters, but what it provides for you.

The space doesn't matter?? Tell that to your fish and corals when they're all jammed together with no room to swim or grow.


OK, so what bad things are going to happen, or what good things aren't going to happen, if fish are added too soon?
Of coarse, nothing 'terible' is going to happen :wink: but it is very good to add fish and corals only to a matured DSB. Why add any sort of fish or coral to anything but a matured tank? A DSB will take 6 months to become fully functional, and matured. I would never recommend adding anything to a DSB until your tank is a minimal of 6 months old. Like I said, nothing 'awefull' will happen :roll:

PH =)

So, if nothing terrible is going to happen, what's your reasoning for recommending this? I have a hard time accepting things just because someone says it's so. Give me a reason. I'll listen.

I'm not sure why you took my comments so personally. I never said that they didn't work. I merely stated why some people don't use them.

Actually I have one in my sump. But, I can close the doors so my guests don't have to see it. :wink:

[HoopsGuru]

actually i've heard of even 1/2" depth considered a DSB
At 1/2" of depth, it can't possibly function as a deep sand bed (a DSB accomplishes both nitrification and denit., the latter can't exist at 1/2"). BUT, I understand why you used the term. :wink:

While I don't agree that a DSB needs to mature 6 months before adding livestock (unless they will specifically feed off the infauna), I don't know why one would use anything else. Other than the agreed fact that it may clash with some people's opinion of "attractive", it is the easiest, cheapest, and most efficient method of filtration of available. Not to mention it is all but "idiot-proof" for beginners. And if 2-4" of extra substrate will really cramp your fish, then the tank is already way to small to begin with.

[phistio]

while trying to keep this thread healthy, and productive...i encourage everyone to understand that we all have opinions...some may differ from others, but they are opinions of those who have some experience with the issue.

DSB's are of much debate because of their relatively new existence to the marine aquaria world. i for one, take Dr. Shimek's research and devotion to the subject as "law," so to speak. some great understanding can be learned from him...visit his website, and see what he has to say about the matter...

http://www.rshimek.com/reef/sediment.htm

[HoopsGuru]

i for one, take Dr. Shimek's research and devotion to the subject as "law," so to speak

Careful, just when you start doing that, the carpet gets pulled out from under you! :wink:

[phistio]

just an opinion...but i would definitely say he's more knowledgable on the subject than i...not to say, if i spent the next five years on the subject i wouldn't be...

[2a]

i have no experience with a marine tank yet, nor have i ever run with a sump tank, but couldn't you just run a really big DSB in a relatively large sump and then put whatever substrate you wanted into the main tank?

[BigE]

I'm not sure why there would be concerns with dead spots in a DSB. A DSB is made deep to create a large dead spot so the anaerobic (without oxygen) bacteria can do the denitrifying. (turning nitrates into nitrogen which is a gas that can then be released into the water column and eventually into the air through gas exchange or the occasional mystery bubble from the sand bed) This is why stirring the sand bed is bad because it releases toxic nitrogen into the water in large amounts and also destroys the anaerobic areas.

Also, silica sand is made of the exact same thing our glass aquariums are. Glass is nothing more than melted and formed silica sand. Silica sand does not have the benefits of a calcium based sand but it does not have the drawbacks that some have worried about in the past.

[Pineapple House]

i have no experience with a marine tank yet, nor have i ever run with a sump tank, but couldn't you just run a really big DSB in a relatively large sump and then put whatever substrate you wanted into the main tank?
You have to think about what goes on in the main tank. Left over fish food, fish waste, detrius, etc will all be in the main tank. Without the proper substrate, this will just rot away. Next, in the sump there must be a return pump. Sometimes the sand in the sump will clog up the filter intake, causing it not to work.

Im not saying it's imposible, but theres just something to think about :-)

PH =)

[HoopsGuru]

I'm not sure why there would be concerns with dead spots in a DSB. A DSB is made deep to create a large dead spot so the anaerobic (without oxygen) bacteria can do the denitrifying. (turning nitrates into nitrogen which is a gas that can then be released into the water column and eventually into the air through gas exchange or the occasional mystery bubble from the sand bed) This is why stirring the sand bed is bad because it releases toxic nitrogen into the water in large amounts and also destroys the anaerobic areas.

You are close, but a little bit mistaken. In a deep sand bed, the depth has to reach a certain point to be COMPLETELY void of oxygen to denitrify. If the sand bed is not deep enough, it will have an area (a/k/a "deadspot") in which it is too deep to for the aerobic bacteria, but ALSO not deep enough to be void of oxygen for the anaerobic bacteria.

Also, stirring a sandbed is not bad, in fact some people without a plethora of infauna do this as maintainance with NO ill effects.

[BigE]

I still don't understand your definition of "dead spot". The top layer of the sand bed is where aerobic bacteria thrives which breaks down amonia to nitrite and then nitrite to nitrate. The next step is done by ANaerobic bacteria that live below the 1 inch layer which breaks down the nitrate into nitrogen. Since nitrogen is a gas it accumulates as gas bubbles which can be seen in the sand bed up against the glass in a mature tank. The gas is also mixed into the water column (just like oxygen) and eventually out of the water and into your living room air. (Just think, you could be breathing fish poop right now)

If you really contemplate this you can see why stirring the sand bed is harmfull for 2 reasons. You are mixing oxygen rich water down into the sand thus destroying the anaerobic areas of the DSB. You are also releasing larger quantities of the nitrogen bubbles into the water column in a small time period causing a spike in the levels of nitrogen which can be harmfull.

The reason we have a DSB is to create these seperate regions which each play an important part of detoxifying the water our fish depend on. Mixing the sand rejoins these two seperate areas causing the DSB to loose its efficiency.

-- Definitions --
Aerobic: Living or occurring only in the presence of oxygen
http://www.dictionary.com/search?q=aerobic

Anaerobic: Not requiring air or oxygen for life
http://www.dictionary.com/search?q=anaerobic

[andrewshafran]

If I were to put the DSB in the refugium, how much of a sand base would I be able to use in the tank before it started to "compete" with the refugium?

Thanks,
Andrew

[LVMAS]

Hello,

I just thought I'd point our additional information for you (i.e. my 2 cents):

Sand Beds - A Natural way of Nitrate, Sulfur & Phosphate Reduction

What are the three layers of a Deep Sand Bed (DSB)? Generally - for colors, presuming one starts with white sand.

Top layer - white, oxygenated region, generally about 1/2 to 1 inch deep.
May have green microalgae, brown or golden diatoms or brown dinoflagellates in it. All or none of the algae are normal and no cause for concern.

Middle layer - tan to light grey. Reduced oxygen region, below top lay to depth of 4 to 6 inches. Bubbles are common here, as this is the nitrogen reduction zone. May have black, purple, red, or green cyanobacterial growth or colors evident. All or none of the algae are normal and no cause for concern.

Lower layer - dark grey to (rarely) black.
No oxygen zone. Below middle region, typically 6 to 8 (or more) inches below the surface. Not much bubble production. Zone of sulfur and phosphate reduction. May have black, purple, red, or green cyanobacterial growth or colors evident. All or none of the algae are normal and no cause for concern.

[HoopsGuru]

BIGE...There is no "dividing line" or Berlin wall that separates the DSB into "aerobic" and "anaerobic". In the transition area, if not deep enough you have an area that is not real efficient at either nit. or denit. Thus it is recommended to go under 1" or over 4".

In addition, I have read accounts of people stirring there entire sandbed or just rotating stirring areas....with no ill effects, kind of a Ripley's moment. Seems some people fear not only the nitrogen gas deep in the sand bed but also a possible buildup of others (there is more than just nitrogen :wink: ). Personally I don't believe that stirring would ever be necessary, but apparently some people do and they do it as part of their maintainance. Even though some stir the whole thing, I don't nor haven't recommended anyone to do so....if someone was to ask me if they should stir it I would say "no, but if you really want to do it in rotated sections"...and would feel confident their tank would be fine.

Andrew, as my opinion states above, either add 1" or less to the main tank or add a DSB in there as well. There certainly won't be any detrimental effect from "competition".

[BigE]

Hoops,
I don't think I've ever heard of this dead zone between the 1 and 3 inch area. I have heard of dead zones being created in the sand bed by clumping. the clumping blocks the movement of nutrients and basically can make a DSB into a SSB (shallow).
To get rid of the clumping we need to add more infauna to the sand who help to move the sand and increase the nutrient processing of the bed.

[HoopsGuru]

I should take the term "dead zone" and toss it because it does lead one to believe that I am referring to the same thing as "clumping". After 1/2-1" of sand bed (water and oxygen rich) you enter a no man's land of sorts until you get over 3" in which you get the full effect of a DSB (denitrification). This no man's land will do nothing beneficial but could lead to a buildup of nutrients in the layers and potential problems. Many believe this is why sand beds are sometimes labeled as having "failed".

Does this mean Phistio's or anyone else with over 1" and less than 4" is going to have a meltdown tomorrow, no.......but it is increasing the chances of having problems occur. If it does nothing beneficial, but could be detrimental...I say-why add it?

[eson]

FAMA Mag for Dec 2002 has an article on sandbeds. It is in part form. Part I covers the basic definitions of the terms. Part II will cover the Berlin method and the DSB.