sand turning black

[joshpwolf]

I used pool filter sand as my substrate. And its starting to get a black color developing on it. Is this normal? Is there anything to do to fix it?

 

[bshenanagins]

Maybe BBA? How long are your lights on?

 

[Cichlid-dude]

Have any pics of it?

 

[sjjennings13]

I used play sand in mmy 20 gallon when I first started saltwater and I had black patches. All my fish died. :/ never found out what it was but did decide not to use tht type of sand again.

 

[Tkey3425]

I was told long ago it was due to silicates in the pool sand breaking down. I've never used it though so that's just what I was told.