Do you people play with your aquatic turtles or just leave them in tank?

The reason people say not to handle turtles is because they often carry salmonella. As long as you don't do anything stupid (like play with your turtles and then suck your thumb), you should be OK, and of course you can always wash your hands afterwards to make sure you're safe. A lot of aquatic turtles will become quite tame if they're handled a lot. I don't see any reason to feed them in a separate tank. Just make sure you have a good filter and let the filter take care of the mess.