Hey I had a similar problem. I posted on here and was accused of being a troll.
There are other posts out there with similar questions and I guess that is why. They felt it was a repeat post. My post is in the fish discussion and it was called black stuff on my sand. I am not sure how to get the link.
I did research and learned that it is the red slime appearing black.
I guess it can take on another color. My started out looking brown too. I did the turkey baster thing and it just broke up. I did manage to use a laddle with holes and shift some of it out but it just grew back. I think it is called cyran or something like that. I turned out my lights for a week and it started to go away. When I thought it was gone, I would turn my light back on and it would be back in an hour or two.
I finally had enough information that the store I shopped at suggested slime eraser. It did the trick in one dose! I was impressed!
Man, this stuff had me baffled and everyone else too. If it is the same thing, this stuff will do the trick and fast. Everyone in my tank seems happy too. It has been a week and it isn't back either. I will try to attach a pic of my tank so you can see what mine looked like. Good luck. I hope this helps. I have replied to others because I think others have the same problem.
I hope it helps!
