Todays tasks involved cutting a final edge to the middle of the star board to match the two end pieces.
I decided that leaving a 1/2" gap on the edges of the sides and front/back of the boards would bring me to the 71.5 x 23.5 inches to match the demensions on the inside of the tank.

I will silicon the board to the tank's bottom. Run an edge of siliscon along the parimeter of each board.
At first I thought oh man my jig saw's blade is broken!


But then I remembered that I bought a larger one during the 2004 hurricane season.