i use hay bags that you would use to hang up in steer pen or horses. whatever. it provides some zooplankton but the bugs are atracted to it.i fertilize to get the plankton. red ear are hard to raise commercially. when i was a kid there was an old fish farmer my dad and i would go see in crockett texas that would keep his catfish heads and grow maggots to feed his small bass and red ear. i dont have acess to large amounts of catfish heads but its a thought.any of you guys know of that old man i cant think of his name.