that little brown guy on the side of my colony is (I'm sure you've probably heard of it) an aptasia and I read that they have a worse sting than any coral and can cause polyps to close up and possibly die.
Hahah wanna trade? But I took them out and clipped off that whole piece of rock that was around it and they seem to be doing good now I have the little aptasia in a small container on my table and it still comes out and opens in the jar hahah