Do you have a picture of your tank set up? Every time I see you post, I cringe. Tropical fish do not belong in an aquarium with a turtle and vice versa. Professionals in zoological nature settings may be able to pull it off, and I once had a friend who constructed his own 55 gallon vivarium with turtles and frogs and goldfish, but he was also an ecology/zoology major. It takes a whole lot of work to keep vivariums. Much harder than keeping turtles and fish seperate.
But I keep getting this picture in my mind that you have this full aquarium with one of those lame floating turtle rafts and this half-dollar size red-eared slider baby while you are trying to keep run-of-the-mill community fish with it. This is just, not a very good idea.
1) Many aquatic turtles are carnivors, so your fish will end up as hor'derves.
2) May aquatic turtles should have cool water to swim in and help them thermoregulate. The temperature will be too cold for tropical fish.
3) All aquatic turtles need some form of basking site and UVB radiation. The basking site should be twice as long and wide as the turtle itself so he can move around on it freely. Most people accomplish this by making their tanks half-land. That leaves precious little water to support fish.
4) Turtles defecate, a whole lot, and they do so in their water. Keeping turtle water clean is a challenge in and of itself, but to keep it clean enough for tropical fish requires real dedication. Turtles will out defecate the fish in their tank.
5) Almost all aquatic turtles are garunteed to outgrow their tanks. I once had a red-ear slider abandoned to my care at an LFS I used to work at. It was a good 14" long, and she didn't even fit the 60 gallon tank I had to put her in for lack of any other space. Luckily I was able to find her a home with someone who owned a large koi pond.
So please, explain much more fully what you are trying to accomplish with your aquarium. It will help us help you better.
~~Colesea