^ +1, about the worse thing you can feed is live feeder goldfish. Give them a mix variety of frozens/pellets. I feed mine smelt, market shrimp, tilapia pieces and floating Hikari stix. I also mix in seachem vitamins on all the frozen foods. It's ok to feed feeders once in a while, but you risk parasite infection and there is not that much nourishment in feeders, especially goldfish.