IMO if the fish look healthy and are eating well then you're just right, if they eat everything you feed them in a short time. I you're having some left overs on the bottom then I'd reduce the amount, on a regular basis. If your fish are eating everything you're feeding them with no left overs, then you could increase it just a bit, but your probably just right. I would recommend a little extra once or twice a week for the clean-up crew, that way they don't start eating each other.