When looking to buy one, make sure they are eating in the store, have someone feed it, and make sure they eat. They are very tricky to get eating. I bought one that wasn't eating from my LFS but now I have him eating live mussles, and clams from my grocery store. In time I will try to train him to eat frozen food. They sometimes pick at corals, but if kept happily fed they shouldn't bother corals.