Here's a tip for you, "A nose heavy plane flies poorly, a tail heavy plane flies once."
If the plane is nose heavy it will not fly really well and will tend to not want to slow down for landing. Once the power is pulled back the airplane will tend to drop like a stone.
If the plane is tail heavy it can become uncontrollable. It will tend to snap out and will most often cause you to crash on landing, especially if you are inexperienced.
Balance the airplane as recommended by the manufacturer. Remember that, although you balance the airplane with the tank empty once you add fuel it will be nose heavy. I personally don't stay in the air until I am out of fuel so my airplanes are always a little nose heavy. How nose heavy depends on how long I have flown. Some of my planes have the tank mounted on the CG but I still balance on the recommended CG.

Regards,
doubledee