I bought my son a small aquarium, and thought that rosy red feeders would be great to put in it, mainly because they tend to be very active and my 3yr old son is fascinated by the movement, however, I have know idea what to feed them.

Any suggestions???????

At pet stores they have goldfish flakes, they will eat those. how many gallons is the tank? how many rosy reds did you buy?

I usually feed my rosy reds with TetraMin flakes by Tetra. Any tropical fish food flakes will work. Goldfish flakes are close enough as well but contain a little less animal-based foods which the minnows prefer. They love live, frozen, or freeze-dried brine shrimp, daphnia, mosquito larvae, blackworms, bloodworms, etc.

mine like my koi pellets.