Greetings Joe, thanks for your interest. Generally speaking, a DE filter offers the finest filtration but usually comes with the highest cost of ownership / maintenance. A cartridge filter still offers a very fine level of filtration, but has fewer components to fail, and has reusable cartridge(s) inside that are easily cleaned and last for years.
If you are a pool professional I'd also recommend checking out our pool professional program by the way. You can also email our pool professional team at [email protected]