I started with a 150 sq ft hayward missle pro cartridge filter when I bought my 24' AG pool and 1 1/2 hp pump. I stuck with it for 3 seasons before changing to a 200 lb poolco sand filter and very recently a 3/4 hp pump that I have been much happier with. I took the advice of some of the other members here and add a cup of DE everytime I backwash and have a crystal clear pool.

The main reason I switched is because I would spend 45 minutes every other week cleaning the filter with a pressure washer (on its lowest setting). I wasn't saving any water by not backwashing because It would take so long to clean even with the pressure washer.

Now I have about the same filtration (with adding a cup of DE) with just a few minutes of backwashing and no bugs, dirt, and other goop that always would end up all over me before I was finished cleaning cartridge.