Mine never touched corals, but man, did he eat. Had to get rid of him. He grew WAY too quickly, (it was a white spotted rabbit) and wouldn't let other fish eat. I got him to get rid of hair algae....boy did he. Unfortunately, he was just too aggressive with the other fish. He stayed at my LFS for about 4 months, and just got bigger and bigger. Finally went to a 500 gallon tank, I was told.