it depends on the actual star; I had a choc. chip with my corals, and he did just fine-I put a clam in and he was on top of him like a dog in heat. I had to take him out b/c of that, and that only. Just keep an eye on him, if he's sitting on top of corals for any decent amount of time, then you should get him out--most LFS will give store credit for stuff like that