Grey/blackish sand??

[cginter]

I bought a fish the other day and used my acclamation box, which redirected the flow, and moved some of the sand bed around... I noticed that the sand under the top layer was greying. Never seen this before but I googled it and some people say it could be some kind of sulfuric something something something... Has anyone else seen this or has had it happen to them, or know what it is and if it's something I should be concerned about. Thanks.

 

[cginter]

Anyway... I siphoned what I could out, it smelled like sulfur/rotten eggs.

I would like to know if this is the sand bed doing its job or if something is wrong.

 

[Tahoe61]

How deep is your sand bed and how old is the sand bed?

Sounds like you just uncovered an anoxic/anaerobic area. While these area of low to no O2 are common in some beds and probably nothing to worry about I would not disturb too much of the sand bed at one time.

 

[cginter]

How deep is your sand bed and how old is the sand bed?

Sounds like you just uncovered an anoxic/anaerobic area. While these area of low to no O2 are common in some beds and probably nothing to worry about I would not disturb too much of the sand bed at one time.

The sand bed is roughly 3" deep in that spot. It is in a very low flow part of the tank. Cyano tends to break out on the sand bed in that spot as well. I figured it couldn't be good after I smelt it. Glad I siphoned it out! Thanks for the info