One more note about the genicanthus angels- I must caution against saying they are absolutely reef safe. My bellus angel started out being benign, until it discovered it's inner animal instinct (or something visceral) and then took a nip here, and a nip there.
So what this does is firstly create a situation of receding coral tissue (especially of my open brain, scoly, etc), exacerbated by reduced chance for the coral to regenerate. What's worse, even if it does, the colour is often not the same as the original