I have a standing column geothermal system, in place since 2010. The well is used for both the heat pumps (4.5 tons) and domestic water supply. System is set up so that all water is pumped into a pressure tank, then through the heat pumps or into house. Return line after the heat pumps to well. Well is 465 feet deep, and has a rate of 2 gpm. While this seems low, I have never had an issue with water getting too cold, or too warm. I can and do bleed about 1 gpm, which is around 10%. I can bleed more, and have never had problems with running out of water, so I suspect the well is actually producing a lot more than 2 gpm. My pumping costs are high, and I suspect it is because the system does not take advantage of the syphoning effect on the return to the well because everything runs through the pressure tank. Is there a way to have a separate pump that essentially just circulates water to and fro the heatpumps (maybe one that is under the house), and let the in-ground pump service the domestic water supply? Thanks in advance for your help!