# Stinky black sand



## mcflyyy (Apr 5, 2008)

Hi All,
My beach sand substrate tank is developing patches of black sand in some places, generally under logs and such. When I vac it out it stinks of rot, so obviously something biological. 
my 3 questions:

1) Is it likely to be patches where poo is collecting and being covered by sand so I miss it when cleaning, then de-composing, or possibly the actual wood de-composing?

2) is it bad? should I get rid of it or will the fish not care?

3) if bad, how do I prevent it?

I don't have this issue in my other sand tank but then that one isn't full of messy severum 

Cheers,
Mcflyyy


----------



## PsYcHoTiC_MaDmAn (Dec 26, 2005)

its patches of anaerobic bacteria. and it is bad.

it can release toxic gas (cannot think what the correct name for it is) which "can" poison the fish.

that said, if you stir the sand through you will release it and get rid of the problem

to stop it happening in the future rake through the sand with your fingers every week to loosen it up and stop the bacteria from developing


----------



## mcflyyy (Apr 5, 2008)

Thanks, will give that a go.
Cheers,
Mcflyyy


----------



## DJRansome (Oct 29, 2005)

Put the logs on the bottom of the tank with no sand underneath. THEN add the sand around the logs. That way, nothing can get trapped. Use a turkey baster to blow into sand where it is difficult to stir with every water change, siphoning up the detrius as you go.


----------

