I finally saw it again - thought I was going crazy. There's a very small creature living in my button polyps -- I tried to take a picture, but zoom isn't strong enough.
From what I could see (with the aide of a magnifying glass and flashlight), it looks like it
might be some type of mini brittle star. It's body appears to be a small black disc, with long, black and white banded arms. The first time I spotted it, I thought it might be some kind of worm, but it's not. I think the button polyp is it's home - have never seen it roaming about.
Any ideas? Haven't looked up in the picture books yet. Thought one of you guys might know right off the top.
Thanks!