Deep sand beds

[goog]

Lee,

I have been researching DSBs and there seems to be conflicting educated research regarding hydrogen sulfide/detritus accumulation and positive/negative effects of sand sifters such as Gobies. From my very limited observation/experience, the Gobies that I have observed aggitated a very limited depth of the DSB.

From a mini-ecosystem perspective (what we are trying to replicate) I would think you would want to aggitate the upper layers since that is what actually occurs in nature.

The upper layer of my DSB shifts slowly (like a sand dune but no dust storm) the result of my power heads and return lines. Is this a little excessive? Should I redirect the flow in order to prevent the shifting?

I would greatly appreciate your opinion regarding DSBs and sand sifters. Is there any reading you would recommend regarding this topic?


Thanks in advance for your advice.

[leebca]

You'll find that DSB are vigorously debated in the hobby.

Probably the biggest concern and the topic most debated is their maintenance. There are those who swear it should not be disturbed; others warn that unless maintained to some extent, it may cause a crash vis a vis a release of built up hydrogen sulfide; and another group that says if you mess with it, you actually create conditions that lead to the hydrogen sulfide release.

The object of the DSB is to create an area of anoxic water -- where oxygen isn't depleted totally, but very much reduced. If the oxygen becomes depleted, hydrogen sulfide is likely produced. However, the hydrogen sulfide production does need organics which can find their way to the anoxic areas by disturbing the bed.

I advise cleaning the top inch of the sand bed and leave the rest undisturbed. If sand sifters or burrowing fishes go below the top inch, then they should not be put in with the DSB.

Particle size is important to the functioning of the DSB. Too large and the anoxic area isn't created or, not enough of it is setup. Too small and an oxygen void may be created which fosters the hydrogen sulfide production. So this feature is important because ultimately, even in the deepest part of the DSB, there is water circulation of a very slow kind! Cut this off and a crash is immenant. (This is why I advocate cleaning the top inch -- to prevent clumping, and clogging of the top layer which may 'cut off' the water flow below).

Regarding substrate drifts, it is probably the wrong kind of substrate for a DSB if it drifts like that. That is, the substrate particle size is too small. The DSB really doesn't do well with fine sand or powdered sugar types of substrates which would easily drift as you've described.

There are probably many different references available on DSBs. I personally believe that there are two people in the hobby with the most knowledge and experience with these kinds of systems. They are Dr. Ron Shimek and Dr. Bob Goemans. Dr. Shimek wrote a pamphlet entitled, Sand Bed Secrets which I think you'll find very helpful. Look for other writings by these two.

;)