When replacing a fountain pump or choosing a new one, first there are some key terms to keep in mind:

"Head": This is the maximum vertical lift of the pump. For example, a 6' head means the pump is rated to pump water up to 6 feet high. Note, however, that at 6 feet the pump would be providing very little water, with gallons per hour around zero. So if you need to pump, say, 200 gph at 72", you will probably need about a 300-600 gallon per hour pump to do the job. See a "pump curve" for the amount of water pumped to various heights.Major pump manufacturers include pump curves on their boxes, brochures, or other literature. You should take a good look.

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