pellet feed should be the primary feed in your system if your goal is to grow healthy fish and plants.. commercial feeds are made for best growth..and as Eleven11 noted... the greens don't break down in the fish's gut as much as pellets.. there's nothing wrong with supplimenting with greens though.. i'm raising carnivorous fish, and i'm working on breeding crayfish, minnows, glass shrimp, gammmaurs, daphnia and green water,, so i agree that adding live food can be a good thing, but imho, a good pellet feed is the first priority.. you can buy 50lb bags for 30-35 bucks from feed mills