Aldo, the Dubro tanks work good. We used 3 24oz. tanks in series on the bottom of the fuselage with the option of using a 4th tank. The thing to remember is to use the gasoline rubber stoppers and also to use 3/16 brass tubing with Tygon gas fuel line.I don't have a copy of the instructions but I think the CG is about 1 inch in front of the hatch. Mike