Painteds require pretty much the same care as RES but tend to be a bit more carniverous. Don't feed lettuce, it has no nutritional value. A good commercial food like Reptomin, crickets, mealworms, collards, dandelion greens, guppies, minnows, etc. Some good care sites are:
www.unc.edu/~dtkirkpa/stuff/overview.html
www.chelonia.org/Articles/chrysemyscare.htm
www.chelonia.org/Articles/bcwaterturtles.htm