Pumps for backyard waterfalls
External and submersible
Pumps are available in external and submersible models,
and each of the pumps has whirling palms that pressurize the water
and push it into a motion. Submersible pumps are easier to use than
external, but more expensive. They are easy to install, they start
without priming, and most importantly, they work quietly.
Before buying a pump for your waterfall, check its electric
rating. Large waterfall request powerful pump, so it consumes more
electrical energy. Choose a magnetic-driven pump, which use less
energy than direct- driven. Usually, the most efficient pumps are
the most expensive, but they can pay for themselves in energy saving.
Size
The most important parameter when choosing
pump is to buy it in the right size. Manufacturers rate electrical
power in amps or watts, but the critical measure is the number of
gallons of water it will pump per hour (gph) to a height, called the
head. To properly choose the size of your pump first, you should calculate
the capacity of water in the waterfall. Usually, the pump for waterfalls
should be able to turn over the total volume of water in an hour.
If you doubt, buy a more powerful pump. You can reduce flow
with a valve. Also, when buying a pump for waterfall; make sure its
head or lift is well above the height you have projected for your
waterfall.
Measuring Gallons per Hours (GPH)
As a pump lifts water to spillway in a vertical pipe, gravity
gives resistance. As the height of the waterfall increases , the gph
of a pump reduces.
The resistance created by horizontal 10 feet water flow is
equivalent to 1 foot vertical rising water flow. For example, if your
pump forces water 30 feet horizontally, that means as 3 feet vertically.
Knowing this, will tell you, that the pump lifts the volume of water
needed, to properly operate a waterfall with the planned height and
distance from the pump. Usually, the manufacturers will tell how much
water circulates at 1 foot . If the height of spillway is between
two listed heights, estimate what you could expect. For example, if
you need 300 gph lifted to 3 feet above the water, choose a pump at
least 300 gph at 3 feet of head. That same pump may circulate at 200
gph at 6 feet of height.
Take measurement of height from the pump, not from the water’s
surface. For proper flow figure 150 gph for each inch of spillway
width. This provides a 0, 5-inch-thick sheet of water over the falls.
Also you need to know how far the water will go horizontally in the
pipeline.
Although variation can exist from rated gph, but not more than
their rated gph. Buy a pump with greater gph than needed. It is easily
to reduce by using valve on the pipeline or a restrictive clamp on
the flexible tubing. It has the effect as lifting water higher in
the line. Some pumps come with a flow valve regulator..
Related article:
Maximize
your waterfall flow with the master DW Waterfall Pump