Depends on the fish I suppose , I feed my malawi's twice a day , my sa cichlid tank everyother day , and my big pred tank once maybe twice a week depending if i think my jardinis gona eat somethin (again lol ) last victim was a wolffish
I went on vacation for two weeks and came back with all my fish fine. I starved them three days before my departure and did a water change on the day i left
Lol i didn't now you need to starve them often, i just put 25 to 50pcs of feeder goldfish (1 to 2 inch size) every 3days to my gar, and dump alot of guppies in my snakehead and shrimps.