I feed my anything meaty anytime I see him at the top of the water near the front.... like for example thawed -frozen shrimp, octipus, squid..he also seems to like that krill that comes in those plastic cans! lol... AND Everysingle time I put seaweed selects on a lettuces clip..he beats feet to get to it..he will hang out all day n all night until he eats it all. I have to feed another sheet to the fish, cuz he hogs the whole thing down!
I have mine in a reeftank, but so far..I have never seen him munching on any of my corals.. I do try to keep him fed...I dont know whether that has anything to do with it or not, maybe its just luck!
hope this helps.
Saltymom