For a koi pond, a practical target is approximately 1–2 complete pond turnovers per hour.
- Minimum: 1× the pond volume per hour
- Typical upper target: about 2× the pond volume per hour, when the filtration and plumbing can handle the increased flow
For example, a 2,000-gallon (7,571-liter) pond would typically circulate approximately 2,000–4,000 GPH (7,571–15,142 LPH).
Aquascape recommends circulating the entire pond volume at least once every hour. Higher turnover can provide additional circulation and aeration, but more flow is not automatically better.
The pump flow must remain within the operating limits of the:
- Skimmer
- BioFalls® Filter
- UV clarifier, if used
- Plumbing
- Waterfall or other return system
Too much flow can cause filtration bypass, overflowing, excessive turbulence, or reduced equipment performance.
Bottom line: Maintain at least 1× turnover per hour. A range of approximately 1–2× per hour works well for many koi ponds, provided all filtration and plumbing are properly sized for the flow.