I know butterfly fish tend to pick at corals, same goes for dwarf angels- It doesn't happen often, but an angel will sometimes pick at a coral or clam...i kept a coral beaty for a while- awesome fish...honestly i wouldn't be too worried about dwarves but i think you should stay away from butterfly fish...have you checked out firefish?Well my two clowns have been in my QT for a couple weeks now...and will be in in there for a couple more...I'm looking ahead to my next fish and was looking between some type of a dwarf angelfish or some type of butterfly fish...I have eebn looking on liveaquria and looking at fish that meet my tank requirements and such...anyhow any thoughts between the two??