There are so many kinds of pumps for the pond: Electric motor driven, magnetic drives, solar driven. There are submersible pumps; we use them most often, but sometimes the same pump can use used out of the water. It's called an in-line pump.
They all do the same thing. An impeller (sort of a propeller in reverse) sucks water in one end and blow it out the other. We use them to power our waterfalls, make our spitters or fountains work or just aerate the pond. In terms of expense, motor driven is most expensive, usually costing about a buck a day to run 24 hours, mag drive a bit less and solar, of course, costs nothing. The solar technology is just now coming into its own, so those pumps would be my choice. Oase is making a line of solar pumps that has a 2 year warranty, a year more than most pumps
I will try one next time I need a pump.
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