apparently i had suction side leaking in plumbing. During that troubleshooting process we found that 2 of the spa returns (they have a "reducer" in the line) were clogged. One of them was actually pulling water from spa into the line. Got those all corrected, and all suction side leaks have been resolved (all o-rings replaced, all check valves replaced, all cpvc connections checked). Pump defaults to 1750 rpm and when the solar kicks in there are "champagne" bubbles from the pool and spa returns after the initial burst of bubbles when the panels prime. 8 panels on single story roof (lowest point @10', highest point @ 16'. VRV is at lowest point on panel closest to pump. Tried increasing pump speed, but the more I increase it, the more pronounced the bubbles are.