is 3 inches of sand a DSB?

[stan]

I have 2-3" of LS at the bottom of my 12 Gal Eclipse.

 

I've been reading up on DSB's and it sounds way too iffy and crash prone to deal with.

 

My main questions....

 

1. Is a 2-3" sandbed considered a DSB? I didnt set out to create one. Should i be afraid of all the anoxic stuff?

 

2. If it is indeed a DSB, can i remove some sand to prevent this from happening or give it a weekly stir and siphon to prevent anything from building up?

 

and last...

 

Will this create a re-cycle of my tank?

[AReeferIsExpensive]

removing sand wont hurt anything...stirring is def not recommended. siphoning sand doesnt sand too successful either.... g/l

[stan]

Everyone always says "dont stir the bed" but doesnt give much explanation why. What is the danger exactly? Will it suddenly release all the toxic crap into the water and kill everything?

 

Also.. my strategy was to stir up the sand bed enough that all the crap in it was floating around and i'd simply siphon up as much of that stuff as i could.

 

Oh yeah.. what would be a good target depth? 1 inch? 2inch?

[halmotors]

Most people say "stir the bed" because they heard someone else say it. The reason you shouldn't stir a seasoned bed is that sulfides tend to build in the substrate over a period of time, assuming there's no movement through the substrate. When you stir the bed up...boom, instant sulfide cloud in the tank. I've personally just used sand-sifting stars in my larger tanks to help keep the substrate stirred up and sulfide free, but in a smaller tank, they may present too much of a bio-load.

[USFnano]

If you do it regularly, it shouldn't be a problem.

[Masoch]

DSB usually refers to a sand bed that's at least four inches deep and contains sand-dwelling critters to make it "live". The sand-dwelling critters necessary to make it function as a good filtration system tend to be worms that live in low-oxygen areas that move through the sand bed to move waste / detritus into the bottom portion of the sand to process nitrate into nitrogen. LR doesn't contain these critters, so LR can't properly seed a DSB ...

 

Also ... these worms won't go within 1 inch of a solid surface (LR, glass, frags) which is the reason DSBs don't really work well in tanks under 30 gallons. There just isn't enough open sand. If you look around here, there are lots of people who've removed sand beds from their nanos for this reason. They really just end up being a holding tank for poop.

[stan]

Makes sense.. so it's either stir it up all the time and never let anything build up or never stir it.

 

Also, this is LS that i bought in one of those prepackaged bags at the LFS. I would assume that it only contains bacteria and any of those worms probably didnt survive the trip from the manufacturer.

 

Luckily my tank is new and i dont think anything has built up in this short a period.

 

Either way, i'm going to remove a few inches of sand and start giving it a stir during my weekly water changes.

[onthefly]

Another thing that comes into effect is grain size. A 2" bed of oolic sand (.2mm-1mm) will provide the same amount of denitrifying power as a 4" bed of .75mm-2mm sand.

 

I have kept DSB in Nanos and larger tanks. They're totally do-able, just maybe not the best thing for everyone. In 6 years, I've never seen (actually smelled) hydrogen sulfide on any of my tanks. People with DSB have consistently had things like PH's and gobies go "haywire" and dig into the DSB.....no ill effects!

 

If you're worried Stan, just do a water change, after you remove the excess sand!