How To Choose The Ideal Waterfall Pump For Your Pond ... Hozelock
Titan Are Good Pump Choice for Waterfalls
There are numerous good reasons to have a waterfall flowing into your pond
... the sight and sound of running water is one of those natural desires most of
us want more of. We all strongly recollect our first sights of a magical
mountain stream, a meandering and cascading brook or small river. And what could
be better than a miniature stream and waterfall in our own garden.
On a more practical pond keeping basis a waterfall allows oxygen to be
absorbed into the pond water replenishing that which has been consumed by fish
and pond filter bacteria. The action of the water cascading from a height in
sheet form is an ideal way to maximise air water contact so that an optimum
amount of oxygen can be transferred from the air into the water.
How Wide Will Your Waterfall Be?
You can imagine the vast amount of water flowing over the edge of the
Victoria or Niagra Falls. Both of these waterfalls are very wide and the flow is
spread more or less evenly across the width or lip of the falls. In fact the
amount of water you need to pump to your own garden fish pond waterfall is based
upon the width of the overflow ledge, lip or cascade width (whatever you choose
to call the actual overflow point). Not all waterfalls have a single lip and
this is very obvious if you've ever been lucky enough to see that wonder of the
natural world, Victoria Falls. You can create small versions of multiple
overflowing waterfalls by placing stones or pebbles
close to the edge. This adds a lot of character.
For Every Inch (2.5 cm) Of Waterfall Overflow You Need ...
About 250 to 350 litres per hour of water per inch (2.5cms) of lip is a good
rule of thumb to calculate the volume of water you would like to overflow the
edge.
Lets say your waterfall has 3 different overflow points in parallel (in other
words your stream is split into 3 smaller streamlets before overflowing ...
-
First lip width is 2 inches
-
Second lip or overflow point is 3.5 inches
-
The final edge over which water is to flow is
9 inches
To calculate the water flow add the 3 widths together and you get the total
overflow is 14.5 inches
For a mild soothing flow and sound kind to the eye and ear multiply 14.5 by
250 and you will find you need 3,635 litres per hour flow rate of water to be
delivered by your pond waterfall pump. If you prefer to work in gallons per hour
then use 50 gph per inch or 2.5 cm of overflow.
If you think you would like a stronger flow then instead of 250 lph or 50 gph
use 350 lph or 80 gallons per hour per inch.
Now you know how to specify how much water the pump must deliver. If you
measure the height of the inlet to the waterfall above the pond surface (not
bottom of the pond) then you can accurately specify the pond waterfall pump.
Now all you need to do is consult the pump table or graph to select the right
model. Take a look below using the example of a Hozelock Titan pond and
waterfall solids handling pump.
The height of the waterfall is 1 metre (3 feet) above the pond surface and
the volume of water cascading over the falls is 3,635 litres per hour or about
73 gph using the above example then the correct Titan pump selection would be
the Titan 5500 (this waterfall pump delivers 4,500 litres per hour at 1 metre
head). We could be quite confident this pump would give us a nice looking
and sounding water fall.
A Practical Way To Decide Upon Waterfall Flow for Irregular Falls ... use a
garden hose pipe
It can sometimes be a bit difficult to decide what the actual overflow width
is. Under these circumstances here's a suggested way to work out an accurate
flow rate ..
-
Take an empty KNOWN volume container of about
10 litres minimum ... call this volume "V"
-
Attach a hose pipe to the tap and place the
hose pipe on the waterfall
-
Adjust the tap until you're happy with the
appearance of your water cascade
-
Do NOT change the garden hose tap setting and
then record the time taken to fill the container in seconds and call this
"T"
-
Work out the volume flow rate for the pump you
need from the following formula
-
3600 x V / T
-
If V is in gallons then your answer is in
gallons per hour ... if V is in litres then your answer is in litres per
hour and then you choose the product based upon these units.
EXAMPLE:
Volume of container is 20 litres and time taken to fill container is 10
seconds then water fall pump flow rate needed is 3600 x 20/10 = 7,200 litres per
hour. A Titan 8000 will probably do the required job (flow at 1metre = 6,800
litres per hour). The next bigger model would be the Hozelock Titan 12000 which
provides 9,000 litres per hour at 1metre head.
If you only want a fountain for your pond you might prefer to choose a
pond and fountain pump such as one from the
Hozelock Cascade products range ... these pumps are perfect for fountains and
come with all the attachments you need to create a beautiful oxygen enriching
fountain display for your pond water feature.
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