Unknown black stuff on LR. Problem?


Premium Member
I've got unknown black stuff on one rock. It was on the dry rock when I bought it. Is it bad? Here's a PIC.


New member
This is known as dieoff. This is normal for live rock, no worries.

You will however have to "Cure" the rock before putting it in the tank with fish/corals.

Wish i could type the full procedure, but i have to run. research "curing live rock"