Mine eats about anything. Pellets, mysis, krill (lots of them), but really loves squid.
Squid's easy cause I can take a big chunk and set it low on it tentacles. Just be careful, those things will stick to you. I've never felt a sting, but I'm more worried about hurting it when that happens and I have to jiggle them off my hand.
Biggest problem I have feeding them squid is that my scarlet cleaner shrimp will take it, so I usually feed him (by hand) a nice sized piece. That keeps him busy while the condy eats.
My parrotfish (who isn't intimidated by it) will snatch mysis right off the tentacles too. So I always feed the fish first, then keep a close eye until he's eaten.
I stopped feeding mine for a few weeks because he was getting big - too big for comfort
He did shrink back a tiny bit.
If I decide I want him to split, I'll probably start feeding every few days.