When's the last time you changed the Sand in Your pool Filter?

Roughly this should be done every 4-5 years as the media breaks down making it non-effective no matter how much you backwash or put chemicals in. Doesn't take to many hot days in Phoenix for the pool filter not to keep up, and before you know it you have a green pool. We upgraded this customer to way more efficient cartridge filter, and cleaned up the hamster maze for piping.