BigB. I came up wit the same answer as Bob. It takes alot of energy to throw water into the air. Think how high into the air you could throw a 5 gallon bucket of water.. You are expecting a motor to do that. The higher into the air you throw water the more energy it takes. It takes lots of "work energy" doing that. It is much easier to move water through the water than it does to lift it high above the water's surface.

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