With the lake drain-down date looming near, I finally got all the 1.5" pump lines connect, wiring in place, filter assembled and installed, the waterfall finished (for now, anyway), and was ready to see if everything would work. The pond was full of water too. First I got down in the water and worked for about 2 hours picking out all the leaves and debris. Then I climbed out, and surveyed the situation. The liner edges were all still exposed, dirt not yet shoveled back in on top of the hoses, boards not yet replaced on the deck. But it ought to hold water. And if the waterfall worked as it should, and if the pump were big enough, etc, etc...it ought to work. I plugged in the pump, and stood back and waited. Voila, it WORKED!!!