What size of filter / sump? (there are several good ones in this forum)
Any permanent residents in the pond?
Pond in the sun?
Nobody home / low sun - 600gph to 800gph (water movement)
A half dozen 3" g.fish / low sun - 800gph to 1000gph
2 dozen g.fish / low sun - 1000gph to 1400gph
3 twelve inch koi a half dozen g.fish / low sun _ 2400gph to 3200gph
Full sun with fish add 1000gph
2 turtles add 1000gph
Lots of leaves and trash getting in - clean it, filter won't help.
If you have water features (spitting fish or frogs) put those on a separate pump and timer or switch and use when needed, so filter can run 24/7/365.
Please note: these are all bare minimums. any and or all can be doubled or tripled with no ill effects.
Dr Joe
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