Originally Posted by FishinRod
I almost never disagree with Theo (he is an engineer and I am not), but I do not believe your pump is "lifting" water from depth. The rule of thumb requiring more energy to lift water means to lift it against gravity. For example a water well supplying 100 GPM with a producing water level of 300' below the surface will require much more energy than a 100 GPM flow with a producing water level of only 100' below the ground surface.
A good point. I believe there would be some additional energy required to move the water through the additional length of pipe that has to extend farther down into the pond, but that would be fairly minimal. It's been either too long (or not long enough) since I took Physics.

Has anyone ever actually pulled water from down deep? That would be interesting to hear about.

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