Saw that on your thread, but trying not to raise my plants any higher. I think they make check valves that only open at a certain amount of pressure. So, idle, there wouldn't be enough pressure to open them until the pump comes on???
Also saw a setup where someone put in a floraflex air bleed valve higher than the res and plants. So, the solution goes from the res, through the pump, then up, through a filter and the air bleed valve, then drops down and to the plants. Will look for that vid and will post in a few