Brine/mysis. I just recently got the Angel to eat pellets (The lo eats everything). Last night I grabbed up the blenny and put it in a bucket with tank water tried to target feed flakes, pellets, mysis and brine. Tried tying some algae to a rock and putting it in with him, but he was just not going to have it.
I've got ocean nutrition prime reef flakes and New life spectrum pellets.