Hay Shanley!! Nice little gal. I believe you have a midland painted turtle (Chrysemys picta marginata). I had one for years. They are pretty omnivorous, they will eat vegetables like lettuce, duckweed, and flesh like worms, night crawlers, fish and about anything they can get. Mine was in a tank with enough water that I could just toss in a bunch of minnows or guppies and it would catch them itself. With a large tank you could set up an under gravel filtration system that would work pretty well to keep things clean and the fish alive (not that it matters to the turtle). Needs a dry spot and a basking light. Remember this is a native species, and it will try to hibernate during the winter, so you should take that into consideration. I like turtles too. Have fun.