I've used mysis and that works well. I used to use my own DIY frozen mix but recently found that some ingredients had high phosphates in them so I won't put it in my reef tank anymore. I only use it for my fowlr.
I turn off all my pumps, feed the fish first (by that time the corals have feeding tentacles out already, plus the fish aren't hungry so they won't steal the corals food) and gently drop a few bits of food onto the tentacles. I try to make sure they have plenty to eat without going overboard. I leave it for about half an hour or so then turn the pumps back on :)