I feed all my fish (percula included) once in the morning and once at night. I feed then flake food mainly, and sometimes freeze-dried food (brine shrimp of bloodworms) as a treat.
I feed flake with spirulina algae and once a week frozen Marine Cuisine. I don't like to use bloodworms because they are not a part of the marine diet. I feed 4 days a week as opposed to my freshwater that i feed 6 days a week
I know some people who hardly ever feed their saltwaterfish.. Given a big enough tank, plenty of LR, and not to many fish.. they can find most of the food they need in the tank