I feed them every 2-3 days. It keeps the nitrates down, and the fish are quite fat & happy; they find enough to eat in the tank otherwise (plus they graze on algae more that way). But please note, that's with my population--includes a flame angel, maroon clown, yellow candy hog, a blue damsel, 6-line wrasse & mandarin. These are all fish that can fend for themselves or get enough out of the fuge. If you had fish like anthias, they would need special care and more frequent feedings.