Pond Volume Calculator
A key piece of information you'll need to know before buying any pond pump, filter or UVC (Ultra Violet Clarifier) is the pond capacity (or volume). This pond volume is usually calculated in litres and can help towards determining exactly what capacity of pond equipment you'll need.
If you don't already know this figure, then you can find it out using our pond calculator below.
What dimensions do I need?
Different shaped ponds require slightly different measurements.
If you have a round pond, you will need the radius and average depth.
If you have a triangular, rectangular or misshapen pond, you will need the average length, width and depth of the pond.
Include All Pond Tiers
If you have tiers in your pond, for example a small raised pool for a waterfall, please make sure that you get volumes for each pool of water and add them together before looking at pond equipment.
How do I find the averages?
Length & width:
Getting this average is easy - simply walk down either the width or length then, each time the pond shape changes, take a measurement. Once you have walked the full length, or width, add them all up and divide it by the number of measurements taken.
Unless you know the different set depths, for example on a yet unfilled pond or if you're building a new pond, a similar method applies for your depth. To find out the average depth, you will have to use a measuring stick and measure at set distances; the more measurements you can take the more accurate the calculation will be.
Using figure 1 as an example: we have four lengths (15m, 8m, 10m and 15m), add these four lengths together then, as we have four measurements, divide them by 4. This leaves us with an average length of 12m. We then have three widths (15m, 5m and 10m), add these three widths together then, as we have three measurements, divide them by 3. This leaves us with an average width of 10m. Finally the depth. Because of the longer length, we would take a measurement every metre (giving us, for example, 5 measurements at 1m and 8 measurements of 1.25m). Add these twelve measurements up then, as we have twelve measurements, divide by 12. This leaves an average depth of 1.25m.
What affects the pond equipment I use?
It's important to note that, although you may have your pond volume, there are 3 factors that can affect the filter and UVC you will need. Luckily our pond volume calculator factors these in for you.
The first two factors that will have an effect on the equipment you need are: a shallow depth and direct sunlight. If your pond depth is below 0.7 metres OR in direct sunlight, then you will have to add 25% to your pond capacity calculation. These lower depths or higher temperatures mean that the pond is more susceptible to things like an increase in the rate of algae growth. It's important to note that if your pond is afflicted by both of these, then you will have to add 50% to the capacity calculation.
The other factor that will affect the pond is fish stock. This is the hardest to get right as it depends on the size and quantity of fish, plus the impact fish stock has on pond equipment varies between different pond suppliers. Our pond calculator will help you in getting close, but please be sure to check the specification of the equipment you're buying.
A comfortable space for your fish
It is key that not only is your stocked pond keen to the eye, but also that the fish have comfortable moving space with their fellow fish. Due to the effect that outdoor factors such as cooler temperatures and changes between seasons have on your fish, you'll find that recommended pond stock levels are lower in a pond than in an aquarium.
Once submitted, our calculator will provide you with a well balanced and safe stocking level which will be pleasing to the eye. It will also provide you with recommendations for the size of the pond filter and pond UVC you'll need
Calculating your pond volume
You need equipment suitable for:
* The above figure is for a pond with no fish stock. See below if you have fish stock.
The actual volume of your pond is litres
Have fish stock?
The total optimal fish length for your pond is cm. This works out at around fish (with an average length of 61cm).
For the optimal level of fish you will need pond equipment suitable for litres.
Alternatively, if you'd like to go for less fish, you can see products that are for a low stocked pond. The pond equipment should not exceed half of the length stated above.
For low stocked ponds you will need equipment for litres.