I've 200 fish & soft corals tank. Three big Angels ~4 years old
( Majestic, Queen, and Emperor). They do not fight or nip my corals but....
I feed them spirulina pellets - morning and seafood banquet at night.
I don't think they can gulp down any more. Filtration? Heavy duty(UV, skimmer, Ecco System with plants and few other good thinks...) Fat and happy, and my corals in one piece.