A general rule of thumb to follow when feeding your betta fish is to not feed them any more at once than they can consume in two minutes. If you feed them twice per day then 2 minute feedings are ideal. If you feed them twice per day, well, do the math. In all reality, if you only feed them once per day, a 3.5 minute feeding session should be enough, but you can push it to 4 minutes if you feel like it. Fish can get fat if you feed them too much so be sure not to over feed them.