With any of the angels you always have a chance that they will nip at clams, zoos, polyps of any other corals in your tank even if in the wild it's not what they feed on. In a close system everything and anything can look like food.
please ,dont make a mistake...
i got one 1,5 ago and he was nipping on my sps polyps..i tought iwas gonna rip off my hair)) took me 3 month to catch this little buster..
I had one in my reef a few years ago, never seen it bother anything. But like Mike said, Angels are typically not reef safe and they will find something you wish they don't touch to chow down on.
My regal angle ate all my zoas(as planned) and moved on to my clams (all eight of them), taking chunks of their mental as snacks. Now I have to figure out how to get him out without destroying my tank.