Several months ago I bought (what I was told) a red knobby seastar. I can't seem to find on that looks like this one. From my research it shows that red knobby seastars can eat clams. The one I have really gets around my tank, and I have seen it on each of my clams. It was only on the shell and never touched the mantle (from what I saw). I just wanted to see what you guys think. I don't want to lose my clams, but I really do like the star. So if it may not be a problem I would like to leave it in the tank. Again it has been on every clam I have and has not done any damage to them that I can tell.