Breeding enough fish to feed that lot sounds like a ridiculous amout of hard work to me. Why not feed them frozen food? With modern manufactuering techniques it's practically as nutricious as fresh fish and you won't have the possibility of introducing disease from the feeders.
A worm farm will be less work, a lot cheaper to run and will provide more nutricious food than dicking about with a tankful of tiny livebearers. Hardly any fish need to be fed livefood, and definately not hardy, easy to keep species like the ones your keeping.