I run mine constantly on the pond with the koi, the other pond doesn't even have a pump. If you have a heavy fish load or you want crystal clear water, run it more. If you don't mind it looking like, say, a pond, then you really don't have to have one at all.
I think too many people want their pond to look like a swimming pool, artificially clear, but that's a rant best saved for another time!
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Sandy Burrell
Northern Tropics Greenhouse
1501 East Fuson Road
Muncie, IN 47302
www.northerntropics.com
specializing in bananas, heirloom tomatoes and water gardening plants~
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