Pond Calculations Explained
Proper pond planning requires three key calculations. Volume determines the amount of water, which is essential for choosing the right filter and water treatments. Liner Size is crucial, as buying a liner that's too small is a costly mistake. Pump Flow Rate, measured in Gallons Per Hour (GPH), ensures the water stays clear and healthy.
The calculator determines liner size by taking the maximum dimensions, adding twice the maximum depth (to go down one side and up the other), and adding 2 feet for overlap around the edge.
Pump Sizing Recommendations
| Pond Type | Recommended Circulation |
|---|---|
| Water Garden (Plants Only) | Circulate volume once every 2-3 hours. |
| Goldfish Pond | Circulate volume at least once every 2 hours. |
| Koi Pond | Circulate volume at least once per hour. Koi require excellent filtration and oxygenation. |
| Pond with Waterfall | Follow the recommendation for your pond type, but also check the GPH requirement for your specific waterfall weir to ensure proper flow. |
How to Use the Calculator
- Select the shape that best represents your pond design.
- Measure the maximum length, width, or diameter of your excavated hole in feet.
- Measure the deepest point of your pond in feet.
- Click "Calculate Pond Specs" to see the estimated water volume, required liner size, and a recommended pump flow rate.
Frequently Asked Questions
How do I measure the average depth?
This calculator uses the maximum depth for the liner calculation to ensure it fits. For volume, it uses an average depth assumed to be about half the max depth, which is a common estimating practice for bowl-shaped ponds.
Why do I need 2 feet of liner overlap?
You need at least 1 foot of extra liner on all sides of the pond. This overlap is anchored down with rocks or edging material to hold the liner securely in place and prevent it from slipping into the pond.