want to build a passive solar heater for my green house,made panels from sliding glass doors,where does pump g

Question

have a water tank,500 gal.s in ground,pump goes where,what side.

Answer 1

If the pump must lift the water from the underground tank, you want the pump as close to the tank as possible so that the water goes from the tank to the pump and then to the rest of the system. You want as little resistance to flow as possible between the tank and the pump.

Answer 2

From tank to pump, from pump to solar panels, from panels to radiators in greenhouse, from radiators back to the tank. If you can rig slow-speed fans to blow air past the radiators, it will increase their efficiency.