Your tank its a very good one, but again dude you need to get rid of that rock assemblage unless its a one peace artificial one or several rocks glued together. Turtles are very strong even as small ones and the risk is not worth it. It can easily wedge itself and not being able to get out, cause the rocks to fall, etc.
By the way this guys LOVE to eat veggies, even as small ones. Try to float a bit of turnip greens on the tank.