How To Calculate Your Pond Capacity

It is important to calculate your correct pond capacity, to enable the right level of filtration to be chosen for your pond and to provide a guide as to the minimum flow rate required in conjunction with any pond filter.

When buying pond products online, it's important to calculate the correct amount of water in your pond as this will affect the type of filter, pump and treatment that will be required to efficiently maintain the water and ecology for your fish. Use our handy calculator to work out your pond capacity.

Step 1

The easiest way to do this is to measure the length, the width and the depth of your pond in feet.

If your pond is not a regular shape you will need to work out the average of all sizes and use this to calculate the capacity.

Step 2

Once you have all three dimensions, you need to multiply these all together and then multiply this calculation by 6.25.

e.g. a pond that is 10 feet long and 10 feet wide and 2 feet deep would use the calculation: 10 x 10 x 2 = 200

200 x 6.25 = 1,250 gallons (remember this is a guide!)

Pond Water in Litres

If you require this capacity in litres which most companies now work with, you will need to multiply the number of gallons by 4.5.

e.g. calculate the number of litres by knowing the pond is 1,250 gallons:

1,250 x 4.5 = 5,625 litres.

Converting Litres to Gallons

This calculation also works the opposite way, to find the number of gallons from the known number of litres in your pond, by dividing instead of multiplying.

e.g. calculate the number of gallons, knowing the pond is 1,250 litres.

1,250 / 4.5 = 277.77 gallons.