I'm still having issues with the spa. The blower is too powerful at 1/2 HP. It blows water over the edge and out of the spa. The distance from spa to air pipe is short enough that I should not need a blower. When the valves are in spa only operation and I turn on the blower than shut it off and remove it from the air pipe I will get a small amout of air flow through the spa jets.
The spa relies only on the main pool pump which goes through the filter. Do I simply not have enough pump to clear the water from the lines? Would a second pump help? I've attached a picture of my equipment setup.