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Going With The Flow: Picking Your Perfect Pond Pump

It’s summertime and we are sitting pondside: beautiful blooming plants, happy splashing fish, cocktails by the soothing sounds of trickling water. Yes, I can hear it all now, or rather, wait, what’s that sound? Actually, there is no sound! Oh no, time for a new pump!


Okay, this is slightly dramatic, but some of us have been there before, and whether you are a long-term pond person or this is your first pond, choosing the right pump can be confusing and make you feel like you need special pond classes to find the right one! Having a properly working pond is essential to the ecosystem of your pond. Your fish rely on you to keep their environment clean; even a pond without fish needs circulation to prevent stagnation.


Here we will help you determine which pump you need for your size of pond and ensure that all your pond features, such as spitters, waterfalls, and fountains, work properly.

Mother Nature Garden Centre-The Perfect Pond Pump-person feeding their pond fish


How big is your pond? Getting the right size pump has several different variables, but always the starting point is how big the pond is. Pond equipment is generally sold in measurements of gallons, so let’s figure out first how many gallons you have. Below are some examples to help you figure out your pond volume in gallons.



  • For a Rectangular Pond:

-Multiply length x width x depth (in feet) x 7.5

-Let’s use an 8-foot-long pond that is 4 feet wide with a depth of 2 feet.

-8’ x 4’ x 2’ x 7.5’ = 480 gallons

  • For a Round Pond:

-Multiply diameter x itself x depth (in feet) x 5.9

-Let’s use a 4-foot round diameter pond with a depth of 2 feet.

-4’ x 4’ x 2’ x 5.9 = 188 gallons

Mother Nature Garden Centre-The Perfect Pond Pump-assorted backyard water features

The Technical Details 

We know this part is not as fun as the sipping cocktails part, so let’s get it out of the way and get back to happy hour as soon as possible!

Some terms to know: 

  •   GPH = gallons per hour.
  •   Flow Rate = the volume of water moved per rate of time (GPH)

-Flow rate can vary depending on how much head height you need; the more water you need moving, the stronger the pump required.

  •   HH = head height

-The maximum height that a pump can achieve.
-Each 10’ of hose = 1HH
-Each 90° turn = 1HH

The Trickling Sound of Water Features

A plain pond with no water features can be, well, pretty plain, so let’s add some fun to it and learn how to calculate the right pond pump for some water features.

Mother Nature Garden Centre-The Perfect Pond Pump-pumps for water fountains

Water Fountains: For flow rate, measure the diameter of your fountain outlet; for every inch, add 100 GPH. For HH, go for 1.5 times greater than the vertical size of your fountain.

Mother Nature Garden Centre-The Perfect Pond Pump-pumps for waterfalls

Waterfalls: For the flow rate, measure the width of your spillway; if you want a moderate cascade, you need 150 GPH for each inch of width. To have a robustly falling waterfall, plan for 200GPH for each inch of width. For HH, measure from the surface of the water to the top of the waterfall. Measure all your hose and count any 90° turns. Every 10 feet of hose and each 90° turn = 1 HH.

Ponds with fish:
For the flow rate, you need to move your entire pond volume every hour. So, for example, a 480-gallon pond needs a min of a 480 GPH pump. When using pressure filters, add 3-5’ HH; for external UV sterilizers, add 2’ HH.

Calculating Decisions

Now that you have a good idea of how to calculate your flow, GPH, and HH, you can successfully decide which pond pump is perfect for your pond.

Deciding what you want or need for your pond is important before you make your purchase: consider whether you want a waterfall, water fountains, and internal or external filters and UV sterilizers.

Mother nature garden center - picking the perfect pond pump-going with the flow

Before you shop, here are a few figures you can have ready:

  • Calculate your total pond gallons and total GPH
  • Determine your water fountain GPH and HH
  • Determine your waterfall GPH and HH
  • Decide if you are keeping fish, decide which type of filtration system you need, and then the HH needed to run it.
  • Add everything up and head to Mother Nature!


Once you have all your information, choosing your pond pump becomes easy. Pond manufacturers generally have easy-to-follow guidelines and charts for each pump which tells you how many GPH it will move with different levels of HH. 


For more information and help with pond pumps, visit us at Mother Nature! We’re always happy to help.