I have a royal gramma, perc clown and "sunrise" dottyback. I generally feed once a day and sometimes 2-3 times a day (rarely) because I like to watch them feed. The r.g. eats about anything I put in the tank as does the dottyback. The perc mostly eats just frozen "formula 1" (the reddish cube).
I generally feed 3 different types of frozen food. I have the formula one which the r.g. likes (but I have it mainly for the perc clown). I also have frozen brine shrimp that I feed and then the other is either a frozen mysis shrimp or a cuisine of some sort.
I cut off small (read "small") portions/pieces/slices of all three and swish it in tap water together, then pour it out through a real fine net (rinses it, the net almost looks like a white t-shirt)(I just recently started rinsing it this way-- before, I did not). I then pour it into a small glass of the tank water and feed it then. The formula one usually stays in small pieces/chunks so I have 8 or 9 small pieces that go into the tank along with the other frozen. I do not pour it all in at once. It is poured in usually over a minute or two.
I also have a dry, flake food that I feed the fish. The perc does not seem to eat this, but the other two do. I just put in a small pinch whenever I feel like watching them eat. I put the small pinch of food still between my fingers and them dip it into the water so that it will go into the water column and not just float on top.
This is "my" feeding regime and seems to work quite well for my three fish. The perc, I've had/fed him this for 6-7 yrs now. The other two, I've had 2-3+ yrs now and have fed this way/diet.
As an edit, I have read that most of our fish this size have a stomach about the size of their eye, which generally means that most of us overfeed. But that is OK for me as I like to watch them eat.
Good Luck, Frank