In my strive for perfect pool water I looked to better filtration. I want cartridge quality with the simple maintenance of sand. What I found was even better. We have found a product referred to AFM - Activated Filter Media. This is a lifetime product guaranteed not to break down like sand over the years and perform even better than a cartridge. Better filtration means less chemical use. Less chemical use is good for not only the wallet but the environment as well. If you are in the market for a new pool filter I highly suggest you take a look at this upgrade.