DE Filter vs Sand Filter vs Cartridge Filter — Which Is Best?

The Short Answer

All three filter types work. The question is which trade-offs suit your pool and your tolerance for maintenance.

How Each Filter Type Works

Sand Filter

A sand filter tank contains a bed of #20 silica sand with a grain size of 0.45–0.55 mm. Pool water enters the top of the tank, flows down through the sand bed, and debris too large to pass through the grain gaps gets trapped. Filtered water exits through the laterals at the bottom.

Sand filters are cleaned by backwashing — reversing the water flow to flush trapped debris out of the sand bed and out through the waste line. Backwash when the pressure gauge reads 8–10 PSI above its clean baseline. The sand itself needs replacing every 3–5 years as it wears down and loses effectiveness.

Filtration limit: 20–40 microns

Cartridge Filter

A cartridge filter uses a pleated polyester fabric element (similar to a car air filter) to trap debris. Pool water passes through the pleated element from the outside in, and particles get trapped in the fabric.

There is no backwashing. When the cartridge loads with debris and pressure rises, you remove the cartridge, hose it off until clean, and reinstall. Full cartridge sets need replacing every 1–3 years depending on pool use.

Filtration limit: 10–15 microns

DE Filter (Diatomaceous Earth)

A DE filter uses a series of fabric-covered grids coated with diatomaceous earth powder — the fossilised shells of microscopic algae. The DE powder forms an extremely fine layer that traps particles the other filter types miss.

DE filters are backwashed like sand filters, but with one extra step: after every backwash, you must replenish the DE powder through the skimmer to re-coat the grids. Without fresh DE, the filter grids cannot filter effectively. For the full procedure, see our how to backwash a DE filter guide.

Filtration limit: 3–5 microns

Head-to-Head: The 6 Key Factors

1. Water Clarity

Winner: DE Filter

DE filters produce noticeably clearer water than sand or cartridge. At 3–5 microns, they capture particles that are invisible to the naked eye — including many algae spores that cartridge (10–15 microns) and sand (20–40 microns) filters miss.

If you have had recurring algae problems or persistent cloudiness despite correct chemistry, upgrading to a DE filter often resolves it. The visual difference between a well-maintained DE pool and a well-maintained sand filter pool is real — noticeably bluer, clearer water.

Cartridge filters provide visibly cleaner water than sand, though not as clear as DE.

2. Maintenance Effort

Winner: Cartridge Filter

Cartridge filters have no backwashing and no media to replenish. When the pressure rises, you pull the cartridge and hose it off — a 15-minute job every 4–6 weeks. Annual deep cleaning with a cartridge cleaning solution once per season. Replacement every 1–3 years.

Sand filters are medium effort: backwash when pressure rises (a 10-minute job), annual chemical filter cleaning, sand replacement every 3–5 years. For the full backwash procedure, see how to backwash a pool filter.

DE filters are the highest effort: backwash when pressure rises AND replenish DE powder after every backwash, plus annual grid inspection and occasional full teardown to clean the grids.

3. Running Costs

Winner: Sand Filter

Sand is the cheapest filter media at $30–50 per replacement every 3–5 years. A 50 lb bag typically covers a standard 24-inch tank with change to spare. For exact quantities, see how much sand for pool filter.

DE powder is the ongoing cost with DE filters — typically $20–40 per backwash depending on your filter size. If you backwash once per month during a 5-month season, that adds up to $100–200 per season.

Cartridge replacement costs depend on the filter model — budget $50–150 per cartridge set every 1–3 years.

4. Upfront Equipment Cost

Winner: Cartridge Filter

Entry-level cartridge filters start around $150–250 for above-ground and small inground pools. Sand filters start around $200–350. DE filters are the most expensive at $300–600 for a quality unit.

All three types have higher-end models that cost significantly more. For large inground pools, budgets converge — you are spending $400–600 regardless of filter type.

5. Handling Heavy Debris Loads

Winner: Sand Filter

Sand filters are the most robust option for pools that accumulate heavy debris — pools surrounded by trees, pools used heavily by children, or public/commercial pools. The sand bed can handle large volumes of debris before backwashing is needed, and backwashing is fast (2–3 minutes).

Cartridge elements clog faster under heavy debris loads and require more frequent cleaning. DE grids can clog with debris and organic material that makes backwashing less effective.

For high-debris residential pools and any commercial pool application, sand is the practical choice.

6. Water Conservation

Winner: Cartridge Filter

Backwashing a sand or DE filter wastes 200–300 litres of water per cycle. In water-restricted areas or during drought conditions, this adds up over a season.

Cartridge filters use no backwash water at all — the cartridge is rinsed with a garden hose and the rinse water can be directed to a garden (it contains pool water diluted by hose water, not concentrated backwash waste).

Which Filter Is Right for Your Pool?

Choose a Cartridge Filter If:

• Your pool holds under 30,000 gallons
• You want the lowest day-to-day maintenance
• You are in a water-restricted area
• You have an above-ground pool or small inground pool
• You want better clarity than sand without DE maintenance

Choose a Sand Filter If:

• Your pool holds over 30,000 gallons
• Your pool is surrounded by trees or collects heavy debris
• You want the lowest long-term media cost
• You prefer a simple, durable system that is easy to service
• You run a commercial or semi-public pool

Choose a DE Filter If:

• Crystal-clear water is a priority
• You have persistent algae or cloudiness issues
• You are willing to spend 20 minutes after each backwash replenishing DE
• You have an inground pool in the mid-to-large range
• Your pool has high bather load (more bodies = more fine particulates)

The Hybrid Option: ZeoSand and Filter Glass

If you have a sand filter but want better filtration, consider replacing the sand with an alternative media:

• ZeoSand — zeolite mineral media that filters to 5 microns in the same sand filter tank. Costs about 3x more than silica sand per tank but provides DE-level clarity without the DE maintenance. Requires annual salt backwash to recharge.
• Filter glass — crushed recycled glass that filters to approximately 3 microns, lasts 5–10 years vs 3–5 for sand, and resists biofilm. Weight per tank is lower than sand (useful for older filter stands).

See our what type of sand for pool filter guide for the full comparison of all three media types.

Related Guides

• How to Backwash a Pool Filter — procedure for sand and DE filters
• How to Backwash a Hayward Pool Filter — Hayward ProSeries specific
• What Type of Sand for Pool Filter? — #20 silica, ZeoSand, and filter glass
• How to Change Pool Filter Sand — step-by-step replacement
• Sand Filter Complete Guide — all sand filter topics