Water for a Red Ear Slider

My brother, who is only 7, just got a big turtle thing, and I've been left to care for it. I wasn't there when he got it, so I didn't get to see where it was being kept. I know I'm supposed to put water in the tank and a place for him to get out. I only put enough water in to barely cover his shell. So..does this thing like to swim or something? I'm afraid of drowning him if I put too much water in without knowing. Oh, and how often should he be fed? We bought some feeder fish and these little turtle pellet things. I left a fish in the tank, but he hasn't eaten it yet..

We have three sliders as well. Yes, they like to swim, but they are air breathers and need areas where they can get out of the water and dry off. The guide for water depth is the diameter of their shell, although slightly deeper than that is fine. Don't feed the turtle in the enclosure, though, as it can make things really nasty and you'll have to clean it way more often. Feed them once or twice a day in a separate place. We use an old metal biscuit pan, and add about an inch of water. They don't make spit, so they have to eat in water. A pinch is plenty for them, and they will eat until they are full, though sometimes they will overeat and spit some out. As young turtles they are primarily carnivores, but the turtle pellets work just fine. Whether they will eat the feeder fish depends on their size, and dietary preferences . Some turtles are big vegetarians, and don't seem to care for the fish, so love to eat them- they just have to be big enough to do it.