I have a 3 tiered pond with 2 waterfalls approximately 900 gallons. the main pump pumps about 2500 gallons/hr. The largest of the ponds approx 450 gallons I have a canister filter with uv with a 600gl/hr pump which I would like to put koi in. Can I run the main pump for one hr then off for 2 to 3 hrs. The upper ponds will only have plants.