Polar Aurora New Pond Pump Adjustable Submersible Inline Fountain Waterfall Koi Filter (1374GPH) 792GPH~4226GPH Is Available,A Total Of 12 This pump is good for waterfalls, pond filtration systems, or any other pond application Flow rate is adjustable(except 2641GPH\3170GPH\3698GPH\4226GPH) Energy saving up to 60% with electronic frequency conversion technology Allow large size of dirt particle up to 1/4