I have a 22,000 gal IG with spill over spa and swim out. So take this for what its worth. Went with upgraded system. 2spd pump, 500lb sand filter and SWG. By upgrading the system I went from 1 skimmer, main drain, 2 returns in pools and 1 1/2" pipe, 1.5hp pump. To 2 skimmers, 2 main drains, 4 returns in pool and 2 1/2" pipe. Run the pump on High for 1hr then low for 8 and high for 1hr. Has worked very well so far. Pool was finished last August so still playing. I also had them add a autofill, overflow drain during construction, I did the plumbing for this. No charge for installing it in the pool wall.