Well it doesn't actually matter as the amount of heat removed will be the same even if the water is flowing fast.therefore use a smallish pump to save power...will work just as efficient as high flow as long as its not very low or else your livestock will actually feel a cold current in the tank.
Electric Power 375 Watt
Cooling power (watts) 790 watt 10 C drop up to 240 gallon
5 C drop up to 450 gallon Recommended water flow 200 - 500 gph
Cooling Gas R 134 A
Dimensions 15.6"L x 13.6" W x 15.6" H
Heat Exchanger: Titanium
Temperature controller: Digital accuracy 1 degree C, Set point in 1 degree steps.
mnfr range: 750-1900L/h
Depending on pipe run, any head,sytem volume and internal restrictions.
Pump should deliver as close to 2000L AFTER deducting for all losses described.
Use pressure rated centrifugal(return type)pump
Powerhead may work, but with lower confidence levels.
Thermal insulation(lagging) of pipe from chiller to tank if need be.
Based on feedback of owners, including those with failed units , discussions with LFS and importer.