You can feed them algae wafers and leafy greens to supplement their diets. I've kept them for many years. In fact if anyone wants to get great advice or just talk about keeping most any fish, try http://groups.msn.com/AquariumTropicalFishKeepingHobbyists/.
Tell 'em DTop sent you and you're in (I'm an asst. manager there). It's a group of 1000 + members and very active.