I'll feed my fish 3-5 or 6 times a day. Basically whenever I walk by any of the tanks every few hours and of anything I have on hand which would include Tetra, Wardly, Hikari and Hai Feng brand flakes, colour enhancing flakes, staple pellets, colour pellets, Hikari algae wafers, sinking tablets, Omega One spirulina, bulk spirulina, frozen or freeze-dried brine shrimp, bloodworm, daphnia, live bloodworm, brine, baby brine, mosquito larvae, micro-worm, and a number of fresh veggies and a few fruits. Of course not all the tanks get everything on the list. The I probably would have lost all my mbuna a loooong time ago if I fed them the way I do the Central Americans. I let my fish fast for a day or two a week or every other week and have never had a diet related problem...except when I went on holiday that one time and the hungry more aggressive fish decided to make meals out of their more docile and tasty looking tankmates.
I never could stand skinny, hollow-bellied fish.