Personally, I would add some weight to the nose for the first flight. If your plane is too much tail heavy it could wind up being uncontrollable.
Why take the chance? Just ad a little weight to then nose until it's balanced. You can always remove weight later if you want.
You can use just about anything for weights.
to be or not to be,,,tail heavy that is by: Anonymous
it depends on your flying style and preference, I don't mind a little tail heavy for my acrobatic planes, makes the controls react little faster etc, so I would say if it's not extremely tail heavy give it a shot and see how it goes for you..
best of luck