Black patches in DSB

[Nickel]

Hi, I have a DSB consisting of about 3 inches of C0 sand at bottom of tank, followed by 2 inches of C1 sand on top.

Recently, black patches started to be seen growing from bottom of tank upwards in the C0 sand, but it does not extend to the C1 sand above (yet ?).

Can anyone advise what is happening and if not normal, how to rectify the situation ?

[Tanzy]

That's the anaerobic region of the sand bed. The black stuff is hydrogen sulphide. Just don't stir the sand and release that stuff.

[junyong84]

a sign of maturing sand bed?

[Nickel]

That's the anaerobic region of the sand bed. The black stuff is hydrogen sulphide. Just don't stir the sand and release that stuff.

Tanzy, thanks for fast response.

Is it normal and will it gets into the water above a starts another round of chemical cycle ?

Anything, besides disturbing the hydrogen sulphide, I need to do ?

[Tanzy]

I don't think there's anything you can do. It's normal with DSB.

[SharkBait]

I think he said DO NOT DISTURB the sandbed.

[Nickel]

a sign of maturing sand bed?

junyong,

Cannot be maturing DSB. that probably takes months at least, if not years.

My setup about finishing cycling. Amomnia, nitrite, at lowest of colour chats of test kits. Nitrate alos very low, as measured today.

Planning to put in LS soon if tests still shows similar results. When saw the black thing growing, got worried. Hopefully the setup of the DSB is correct.

[Nickel]

I don't think there's anything you can do. It's normal with DSB.

Got it. Thanks. Keeping my itch fingers away from the DSB.