I have a problem with an above-ground water tank supplying a pump on the ground, supplying a sprinkler system. When the pump turns off, the water doesn't stop due to the syphon effect. When I first installed the pump, I put in an adjustable sprink check valve after the pump, but it still leaked and the water slowly ran out. I have removed the check valve. I wonder if I put the check valve back in, and after that a tee with a swing-check to allow air to come into the system when the pump has stopped and the pressure is reduced. I consider doing the swing check in a section of pipe that is higher than the pump. The water tank is 5000 liters and about 3 meters tall. The lines are all 2". I am not able to upload my drawing due to poor internet connection. Any ideas? Thanks!