Red-eared sliders eat both plants and meat. Older turtles eat a lot more vegetation than young turtles, who are primarily carnivorous. Commercial turtle pellets can be fed as part of a turtle's diet but should be supplemented with fresh vegetables and prey animals.
Commercial turtle pellets can account for around 25 percent of a turtle's diet. For vegetation, offer a variety of leafy greens. Good choices include collard greens, mustard greens and dandelion leaves. Kale and bok choy can also be fed to a turtle. Lettuce, particularly iceberg lettuce, has very little nutritional value and should only be fed sparingly. For prey animals, select live worms, crickets, snails, daphnia and krill. Larger turtles can be fed tadpoles and small fish.