hmmm,the Bannerfish... this is a cool looking fish to have , they look very much like a
Moorish idol and live better. what size tank are you going to have him in? i hope something bigger than a 55 gallon.
they are meat eaters( although a mixed diet with greens will be the best), so some of your smaller inverts may become dinner. i have read / heard of them nipping at some
soft corals too. But that is NOT always the case.
should you decide to get a pair ( or more), someone will become the master. you will see some head butting and body slamming until the master is set.