Choosing Waterfall Pumps The Correct way
How To Select Your Waterfall Pump With Total Confidence
Choosing a pond pump to run your waterfall and pond filter can be a bit tricky.
The wrong choice can be costly and disappointing. Make sure your pump runs 24/7
to keep your pond filter working. You only need 2 bits of information then
choose from the table below
1. Vertical height of waterfall inlet above water surface of pond (NOT bottom of pond) ... measure this in feet. This is pond pump head ... see picture opposite.
2. Width of water overflow point for waterfall ... if overflow is series of smaller overflows add all together to get width in inches. This is needed to work out waterfall pump flow required. The picture also shows what is meant by the overflow width ... take note at bottom of picture where you see water flowing over the edge of the last waterfall. This is the waterfall width you need to measure.
The
point about multiple overflow points can be confusing ... this is an example of
a waterfall that has distinct overflows. The main water channel has separated
into 2 clearly visible cascade points. If your own watefall does something
similar then you must add the 2 widths together as described above.
3. PLAY SAFE: Make an allowance (add 20% to the measured head (H)) for energy losses due to pipe bends and fittings
Waterfall Pump Selection table
Check where height meets width in the table. This is the flow your pump model must deliver.
Check where height meets width in the table. This is the flow your pump model must deliver. For a wide range of guaranteed Great range of low priced pumps for small to medium sized ponds and waterfalls
| Waterfall Vertical Height measured from surface of pond ... (feet) .. add 20% for energy losses | |||||||
| Width of Water Overflow (inches) See image above
|
1 ft | 2 ft | 3 ft | 4 ft | 5 ft | 6 ft | |
| 3" | 350 gph | 500 gph | 500 gph | 500 gph | 700 gph | 700 gph | |
| 6" | 700 gph | 700 gph | 700 gph | 700 gph | 1200 gph | 1200 gph | |
| 9" | 1200 gph | 1200 gph | 1200 gph | 1200 gph | 1200 gph | 1200 gph | |
| 12" | 1200 gph | 1200 gph | 1200 gph | 1200 gph | 1200 gph | 1200 gph | |
Example ... you have a waterfall 3 feet above pond surface and overflow is 9 inches wide. You need a pump that will deliver 1200 gph at a height of 3 feet. An example of such a pump is a Danner Supreme Mag Drive 1200 gph as above. If you have a waterfall 24 inches wide and 3 feet high you would need 2 model 1200gph pumps TIP: always go for one size larger if in any doubt ... Danner Pondmaster pumps
In practical situations I would always recommend that you add about 20% to
the height you want to pump to. By doing this you allow leeway for energy losses
that inevitably take place in any real pump circulating system due to bends,
fittings, restrictions, kinks in the line and so forth. In this example
described here the height would then increase form 3 feet to 3.6 feet. As it
happens in this case the original choice is good enough ... the suggested pump
model at 4 feet (ie closest to 3.6 feet) is still the 1200. You can often
improve the performance of any pump by about 20% by using larger diameter pipe
and shorter straighter pipe routes using less fittings and by making sure the
tubing is not kinked or flattened.
GOOD TIP: The best waterfall pond pump pipe you can use is black ribbed piping
which when bent forms nice smooth curves and cannot kink or get flattened
easily. The fact that it's black will also make it more difficult for pond algae
to grow inside the pipe and make a restriction that will reduce pump flow.