I feed in the early AM, before the lights come on, and most of the fish are too sleepy to steal it. Also, when the light are on, corals are concentrating more on photosynthesis, the polyps open up to feed at night, and that is when they'll be more ready to accept it. I feed a little bit of Oyster Feast a few days out of the week, and some Cyclopeeze once or twice a week(more for the LPS). I can get away with more feeding because of my system volume and large skimmer, but I still need to be careful, as too much too often can be counterproductive. Try to resist the urge to stuff them up with food.
As far as Phyto, like mentioned above, it really doesn't feed the corals. It feeds clams, but also feeds pods, bacterias, and all the other tiny and microscopic life in your tank, which ultimately the corals and fish do feed on. I add a little phyto once in a while to keep things going.