Mark,

You mention that there is sufficient flow with the pool water/air mixture to keep the flow switch on. If this is correct than you have the potential to create a hydrogen/air mixture which could be explosive. I am not kidding. Any system of this sort has to have that protection to shut off regardless of who made it. Hydrogen can be very unpredictable in the presence of oxygen. In other words been there, seen it happen. You just do not fool around with hydrogen in the presence of anybody.

Pat