What Size of Pond Pump and
Filter
Should I Buy?
With all the different types of
pump and filter available, it can be difficult to know what to
choose. As a rule of thumb we always use the following:
Nature
Ponds
A pond with lots of plants and no fish (or a few, small native
fish) needs all of the water to be pumped though the filter every 2
hours.
Goldfish
Ponds
A pond with some plants and some fish (mainly goldfish), needs all
of the water to pass through the filter every 1 ½ hours. This is
the most common type of pond.
Koi
Ponds
A pond with few plants and big fish, like koi, needs the water to
be pumped through the filter once every hour.
Example:
If you have a pond of 3000 litres then your pump flow rate will
need to be:
Nature pond – Flow rate is
1500 litres per hour
Goldfish Pond – Flow
rate is 2000 litres per hour
Koi Pond – Flow rate
is 3000 litres per hour
These are the flow rates that the
pump should deliver into the filter so you should also take into
account the distance travelled between the pump and the filter. The
change in height is the most important part of this. Pond pumps are
generally not very good at pushing water uphill as they are quite
low pressure.
Click here to see our section on
choosing a pond pump.
This section on pond pumps talks about choosing a pump that will
deliver the right amount of water at a given height.
Once you know how much water the
pump will deliver to the filter you can look for a filter that has
a maximum flow rate of at least that amount. Getting a filter with
a lower maximum flow rate is not a good idea, as it will usually
result in the filter overflowing.
If your chosen filter is bigger
(i.e. has a higher maximum flow rate) than you need then
that’s fine, it just means you’ll have to clean it out
less often.
To work out your
pond volume, just use this calculation (all measurements are
metres):
Pond Length x Pond Width x Average Pond Depth x 1000 = pond volume
in litres
or
Click here to use our online
calculators to work out how much water is in your
pond
Click here to see our range of
pond filters and pumps
Now that you know how to
work out what size of pump and filter you need, why not take a look
at one of our other guides?
Waterfalls
Pond Filters
Fountains
Connecting the Pond Pump and Pond
Filter
Filter
Maintenance
Electrical supply to the
pond
Adding fish to the
pond
Or click here to see a list of
all our pond building guides
