Chip,
Aren't you concerned about the weight of the ball bearing down? Do you have a plan to suspend the ball or are you planning on just setting the "New Year's Ball" on the bottom, supported by the extending PVC pipes? I, like Ryan, kinda dream of somehow cutting the balls in half...presumably to set them on the bottom like new wave aqua-art. There would be no stress on any of the PVC...it would wind up like a PVC reef.