They are supposed to have some sort of theets that always grow and must be weared down by chewing on hard shell.

Mine is currently with my gold headed goby and they eat side by side and no aggression from either fish. They even toutch each other without any reaction. Mine is around 4" right now.

He has not toutched my flame scallop nor any of my coral so far, keep finger crossed.

I have read they don't attack coral but their natural prey are shrimps and they can eat them once they are adult. I also have a crocea in my aquarium so hopefully he'll ignore it.