I have a spa seperated from my pool by a solid wall. Water does not flow over the wall into the pol. The spa water level is about two feet highter than the pool water level. Both are filtered by the same pump. My problem is getting water to circulate in the spa and keeping a constant water level. My pool service suggests that the builder should have installed an "equalizer line" from spa water level line to below pool water level line, so excess water in the spa would flow into the pool. Any experience with this?