Stick with a sand filter unless you're obsessed with clarity.

Sand filters are the easiest to maintain and good enough for most pools. Cartridge filters are a decent middle ground. DE (diatomaceous earth) filters give you the clearest water but require more work.

The main difference is how fine the filtration is. Sand traps particles down to about 20-40 microns. Cartridges go to 10-15 microns. DE filters get down to 5 microns or less. That’s why DE water looks so crystal clear.

But there’s no free lunch. Sand filters are basically a metal tank full of sand. You backwash them every week or two and replace the sand every 5-7 years. Cartridges need rinsing every few weeks and replacing every couple of years. DE filters need you to add fresh DE powder after every backwash and periodically clean the grids inside. And if you mess up, you can blow DE into the pool.

For a residential pool, I’d get a sand filter and call it a day. If you’re building a show pool or you’re the type who obsesses over water clarity, go DE. Cartridges are fine but not really better than sand unless you have space constraints.

(And yes, you read that