RES are wonderful turtles!
they can eat pinkies (what you feed msot snakes).
http://www.austinsturtlepage.com/Car...ear_slider.htm

they get around 8 or so inches, but females can vary between 10 and 12 inches.
Air Temperature: mid 70's - 80's
Basking Temperature: High 80's to low 90's
Water Temperature: ~ 72 to 76 degrees for sub-adults & adults, 78 to 80 degrees for hatchlings & smaller juveniles.
they will need a much bigger gallon aquarium or surface mount pond.

Mazuri and ReptoMin, Reptile/Pond 10, Cichlid Sticks, feeder fish, feeder crickets, earthworms, krill, blood worms, occasional crayfish & ghost shrimp, aquatic plants (such as Water Lilies, Water Hyacinth, Duckweed, Anacharis, Water Lettuce, Water Fern, Pondweed, Water starwort, Hornwort, Water oil, and Frogbit), some vegetables (such as Zucchini, Squash, Collard Greens, Beet Leaves, Endive, Romaine, Red Leaf Lettuce, Kale, Escarole, Mustard Greens & Dandelions) and some fruits (i.e. Banana). Many keepers use a good brand name commercial diet (usually Mazuri or ReptoMin Aquatic Turtle Diets) for a substantial portion (say, 25 - 80%) of the carnivorous portion of the diet, & round that out with treats of crickets, earth worms, crayfish, ghost shrimp & krill, & use Romaine lettuce (chosen over iceberg for higher fiber) & Anacharis as mainstays for the herbivorous portion of the diet. Since wild RES likely don't encounter fruits often we don't recommend use of Bananas & other fruits except as rare treats. Some people offer hairless mouse pups to turtles on occasion; never feed hairy animals to animals who don't naturally eat them (like RES) since hair is poorly digestible & can form trichobezoars (hairballs) & cause G.I. obstruction in some animals (so in theory perhaps RES).