shouldnt eat urchins...corals maybe...usually softies. and they fish shouldnt fight...but there is always the possibility that u get unlucky and get a mean fish.
there are so many different bflys...i never payed much attention to them do to them not being reef safe. bets thing to do is open a book and find one hat meets ur needs.
Hmmm I just read buttferflies with long noses/snouts prefer to dig in rocks and eat smaller things, while butterflies with shorts noses/snouts will eat larger corals,clams, ETC. Does anyone have anything to say about this?