I've been experimenting a bit with changing speeds on the pump to see which works best with my pool (14000 gallons) and SWG, but still would like some clarification. I was told by the company who installed the system multiple options...one of which was to run at low speed 24/7. However I've noticed after start up if I run at low speed (speed 2 which I changed from factory setting 1500 rpm to 1800 rpms) after a full day or so it appears air bubbles start to appear in the pot strainer lid. Once I kick the speed up to speed 4 (3100 rpm) the bubbles dissipate. Is it possible that at the low speeds I'm not drawing enough water to operate the system efficiently? A service tech did address a small suction side leak at pvc coupling that I discovered by running water over suspect area, but bubbles still appear at low speeds. Also hear some water churning a bit in filter head...not sure if this is normal...again only at low speeds...filter pressure is only about 8 psi at 1800 rpms. Any help would be appreciated as I'll continue to tinker.