Deep Sand Bed

[dillonsshop]

I know I'm going to regret asking this, but how much sand is required to constitute a DSB? Most of what I've read says about 4" average. For my 110 g tall (48" x 19") that means 234 lbs of sand :o ,according to the calculator on the site here. The other thing I have read about is that a SB or DSB needs stirring to keep it from dieing. Is this the case? Seems alot of work. Could you use some animals to dig around in there that don't eat the critters in the live sand? I'm just soo confused. :wacko

[scuba_steveo]

The great DSB question. I have a DSB. And yes it needs to be at least 4" of small grain sized sand. Dr. Ron on reef central has many good readings on DSB and he knows much more about them than any of us here. But....why do you want one? You do need critters to keep it stirred or certain areas will become "dead". You do not want to stir it yourself. This would release gas from dead areas and can hurt the tank. You do not want a DSB to crash...that would be bad. My next system will have a thin sand layer (1") that I can stir and clean without having tio worry about it. I like the ease of bare bottom but I like the look of sand.

[dillonsshop]

The reason I want the SB is because it looks right. But I'm not dead set on it beeing a DSB, just want to find lots of neat critters in it.

[Thunderkat]

If you haven't set up a tank yet give the Jaubert system a shot. Look it up online, I am going to try that, going to put some fish in this weekend.

Does anybody know where to buy some really good live sand?

I bought some but it was devoid of critters.

[StephenA]

Go read Dr Ron's book on DSB's!

[greasemonkey]

What about using a siphon in your DSB? Will that help maintain it?

[TheCampbells]

My DSB is about 4-5in deep and has b been running for just over two years now. No problems yet, and plenty of small critters.

[GaryP]

What about using a siphon in your DSB? Will that help maintain it?

Siphoning will definitely help remove detritus and reduce the biological load on a DSB. However, I think the main concern a lot of people have is with the "health" of the deep layers of the DSB where you can't siphon. By siphoning you are removing the detritus on the surface, not the nutrients trapped in the deep layers.

[StephenA]

The key is to keep critters on and in it. Some cucumbers dig thru it, Hermits are good for the surface, Some snails dig. I dig in mine about every 3 months. Mine gets uneven from flow.

[demodiki]

Buy a tiger goby...your sand bed will be everywhere :(

[Someone]

So would getting some type of goby be enough to sift through the sand? I have a 3 in. sand bed... I only mess with the top inch or so on average when im working in my tank. ;)

[dillonsshop]

Thanks for all the info guys. I'm really trying not to go over board here, but where do the live critters like cucumbers and sand dollars come from? The salesman at the LFS told me that they were in the LS bag that they sell (AGRA_LIVE) and that a couple to four inches was fine. My question then is this: "How do these critters stay alive in a sealed bag?" There are no new nutrients coming into the bag and no fresh supply of air so is the guy just trying to sell me a bag of sand (ie sandbag me) with good bacteria included? <_<

[dillonsshop]

THat is what I thought :angry ! The only LFS in Brownsville is Petsmart. The guy that runs the fish department is the asst Mgr but he is on vacation. His replacement for the week was an IDIOT! I hope I never have to deal with him again. Enough bashing for now. I suppose I'll just order LS from an online store or come to one of the meetings in San Antonio soon.

[GaryP]

Persoanlly, I think the main thing in the Aragalive are bacteria although I have heard that they also contain a large number of micro brittle stars.

[demodiki]

I think my Goby was a Viet Cong tunnel rat in a past life.

[Thunderkat]

I heard sea cucumbers can be haneously bad for aquariums if they are disturbed.

[GaryP]

I heard sea cucumbers can be haneously bad for aquariums if they are disturbed.

Some are, some aren't. You need to do research on each individual species. Avoid braod strokes of the brush when it comes to such a large group of animals.

[matt]

The most important thing, by far, in keepng a successful deep sand bed is knowing which animals to keep in it and which to keep out. For example, a large sifting star will certainly sift your sand, but it is doing so in order to eat the animals that live in it; same with many of the burrowing fish.

The reason for the 4" minimum depth is to provide enough habitat for sand animals to avoid predation and follow their normal behavior. I don't know how set in stone that figure is; I had at one point a sand bed about 3" deep mostly of the pre-packaged "live sand" which is not considered an ideal grain size for a DSB, and there were way more worms and macro-critters in that than in the 4" SD sandbed I had in a later tank.

The principle is simple; if you have enough of the right kind of animals living in the sand, they will continue to process waste from animals above on the food chain all the way down to bacteria processing nitrite into free nitrogen. According to Ron Shimek and other proponents of DSBs, the bed provides habitat for animals that occupy several links on the chain, and therefore ensure that waste is processed all the way to free nitrogen, which then bubbles out of the system. Here's an oversimplified example. Let's say you have fish and scavengers, like some hermits and snails, and some bristle worms living on liverock. Okay, so maybe the uneaten fish food goes to the hermits, fish waste goes to the bristleworms, and some excess nutrients form algae which is eaten by the snails. What happens to the waste produced by the worms, snails, and hermits? In a non-DSB system, theoretically it decomposes and is processed by bacteria; although there is not nearly the same habitat for this bacteria without a reasonably deep layer of sand. With a fully fuctioning BSD, the idea is that the waste produced by the scavengers is used as food by smaller scavengers, maybe microstars and smaller invertibrates living deeper in the sand, and then down the food chain by a variety of microscopic animals such as bacteria. Without a healthy population of these animals, the waste just builds up in the sand and eventually you have a crash.

Although the principle is simple, making it work over the long term is not so easy. First, you need to have a good source of sand, meaning a good source of animals that live in sand. According to Shimek, and it makes sense, you need a maximum diversity of animals living in the sand to ensure a stable and healthy population. BUT, you have to avoid animals which will predate on or out-compete others in the sand for your population to stay diverse. This is the reason for the periodic "charging" with live sand from different sources. Living on the ocean, you should be able to get great live sand, if you can find a clean enough spot, and avoid bringing sand with predators into your system.

Second, assuming you've gotten a sandbed going with a reasonable population of critters, you've got keep them alive, which means enough food for them to survive and reproduce, but not so much that they can't keep processing it all. I personally think finding this balance is not easy, and might be a leading cause of sandbed failure over the long haul. Let's say you have a fairly new tank; you start stocking it, producing waste, the sand bed animals increase in population to match the increasing waste from the larger animals as they grow, and you add more of them, and soon enough you have a healty, growing eco-system. It's stopping the growth without upsetting the balance that I think is really difficult and takes a large amount of patience on the part of the reefkeeper.

Overall, I'm a real fan of DSB systems, because I think they mimic nature well, and the whole process is really interesting to me. But, you have to remember it's an evolving concept in reefkeeping, and it's based mostly on things we don't easily see or understand, unless you're a marine micro-biologist with a microscope to check out sand samples from your tank periodically.

[dillonsshop]

Well for what its wourth I'll be setting up this weekend about a 2" SB and see how it looks for a week or so. If it looks too shallow I'll add more. I'm really excited about getting this thing up and going, and getting the LR out of the spare bedroom. I had thought about "harvesting" sand from the beach here and there are some tanks around here with LS from the Gulf that have been opperating for years and look great. These same people also "harvest" their water at the ocean and have great success. Their claim is that mother nature keeps the micro organisims and other critters more diverse than we can reproduce with buckets of salt. Of course they are also the same ones that tell me not to buy/drive my 1957 Chevrolet because it is killing mother nature. I'll see about posting some pics this weekend of the process, perhaps the wife will post some pics of my corpse if I don't do anything this weekend. Thanks for all the info. It may seem that I ask ALOT of questions without action but I feel strongly that your experience (mistakes) will prevent mine.[/quote]

[matt]

If you can get clean sea water and unpolluted sand from the ocean, you should definitely do it, especially the water. Maybe take a boat out a ways, I don't know if there's any sort of reef around there. Just a small bucket of sand from the ocean would be a big help, as long as it doesn't have any predators like sifting stars or swimming crabs. The animals will soon migrate into your sand. You have to be patient though. Everything I've heard about using seawater is very positive, as long as you can get clean water. You may have to adjust the salinity by adding a little bit of salt mix; do that and let it circulate in your tank, hopefuly getting really aerated, before worrying about ph, Ca, and Alk. After it's been in there a day or so and is fully aerated, check Ca and Alk levels and adjust as needed with turbo calc and buffer, Then see where the ph is a few hours later. Since you're using natural seawater, I wouldn't worry too much about adding calcium and/or buffer to bring the levels above normal; maybe shoot for 400ppm Ca, and dkh of around 7; these are just on the high side of NSW levels, depending on where the water is collected from.

Not sure what this has to do with your 57 chevy....

[Thunderkat]

If you were to run a 57 chevy into your tank it could cause problems.