Choosing the Right Pool Filter: Cartridge, Sand, or D.E.?

A pool filter keeps water clear by trapping dirt and debris. But size and type must match your pool's volume and your maintenance preferences. Here's a breakdown of the three main types.

1. Cartridge Filters

Pleated polyester cartridges trap particles down to 10–15 microns. Low pressure = less pump strain, better flow. Clean by hosing off 1–2×/season; replace every 2–5 years. Best for: spas to large pools wanting polished water with easy upkeep.

2. Sand Filters

Water flows top-to-bottom through special silica sand. Traps larger particles first, then finer as it loads. Backwash (reverse flow) to clean. Affordable, simple, durable. Best for: small to huge pools; DIY-friendly. Filter down to 20–40 microns.

3. Diatomaceous Earth (D.E.) Filters

D.E. powder (fossilized algae) coats grids, filtering to 3–5 microns—clearest water. Most expensive. Backwash and recharge with fresh D.E. periodically. Grids last 5–10 years. Best for: medium/large in-ground pools where water clarity is paramount.

Sizing Matters

Pump and filter must match pool volume. Oversizing slightly improves efficiency. Once sized, choose type based on budget, maintenance tolerance, and clarity goals.