How many times per hour should a pond be circulated?

For filter-fed ponds, circulate the entire volume once per hour. For waterfalls and streams, 1.5 times per hour gives a good visual flow. Fountains only need about 0.5 turnovers per hour.

What is head height and why does it matter?

Head height is the vertical distance from the pump to the highest point the water must reach (e.g. top of a waterfall). Pumps lose flow rate as head height increases, so you need a more powerful pump for greater heights.

Does pipe diameter affect pump performance?

Yes, significantly. Narrow pipes create more friction, reducing flow rate. For flows over 2,000 L/hr, use at least 32mm pipe. Every 90-degree elbow adds roughly 0.5m of equivalent head loss.

GardenCalcs

Pond Pump Calculator

Calculate pump flow rate needed based on pond volume, head height, and feature type.

Pond Volume

Total pond water volume in litres

Head Height

Vertical distance from pump to highest point

Feature TypeWhat the pump will drive

Pipe Diameter

Internal diameter of your hose or pipe

Pipe Length

Total length of pipe from pump to outlet

How We Calculate This

Flow rate = Pond Volume x Turnovers Per Hour. This base rate is then increased to compensate for head height and pipe friction losses.

Total head includes the vertical lift plus friction from pipe length and elbows. A safety margin (default 20%) ensures the pump can handle real-world conditions.

Frequently Asked Questions

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Wildlife Pond Calculator

Calculate pond volume, liner size, underlay, pump size, and planting shelf area for a wildlife pond.

Last updated: March 2026

All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.