Cartridge, sand, or D.E. — which pool filter is best?

Sand is cheapest to buy and easiest to maintain but filters coarsest (20-40 microns). D.E. gives the clearest water (1-5 microns) but is the most work. Cartridge is in between and saves water because it is never backwashed.

Why is my pool filter pressure so high?

Dirt has loaded the media and is choking flow. Clean the filter when the gauge reads 10-12 PSI above the clean baseline pressure. Running it dirty wastes power and can damage the tank.

Why is sand blowing back into my pool?

A lateral — a slotted tube at the bottom of the sand tank — has cracked, letting sand bypass the bed and shoot out the return jets. Replace the broken laterals.

Why is D.E. powder coming back into my pool?

A grid's filter cloth is torn, the top manifold is cracked, or an air-bleed strainer is missing, letting the fine powder through. Find and replace the torn grid.

When should I replace my filter cartridges?

When they won't return to baseline pressure after a thorough cleaning, or when the pleats are matted or the core is collapsing. Most cartridges last 3-5 years.

How do I safely open a pressurized pool filter?

Shut the pump off at the breaker and open the air-relief valve until the pressure gauge reads zero before loosening the clamp. A pressurized lid can separate with deadly force.

My pump runs but there's no water flow. Is it the filter?

Usually not — it's a suction-side problem like a clogged skimmer or impeller, or air drawn in at the pump lid O-ring. Clear the baskets and reseal the lid.

Will running my filter stop my pool from turning green?

No. A filter removes debris but doesn't sanitize. Green water is a chemistry failure — low free chlorine or high cyanuric acid. Fix the chemistry and the filter clears it up.

Pool maintenance

Pool filter types: sand vs cartridge vs DE compared

By Derek Bowen, founder of Pool Rental Near Me and author of 7 books on pool hosting · Updated May 30, 2026

Sand filters down to 20 microns, cost $300 to $700, and need backwashing. Cartridge filters down to 10 microns, cost $400 to $900, and need rinsing every few weeks. DE filters down to 3 microns, cost $600 to $1,200, and need annual teardown plus DE powder.

5 min read · Updated May 30, 2026

Every pool filter is one of three types — cartridge, sand, or D.E. (diatomaceous earth) — and each one traps dirt differently, costs different amounts to run, and fails in its own way. This guide helps you pick the right type, find your exact filter model, and fix the most common problems before you call anyone.

Which filter type is right for you?

Type	Upfront cost	Maintenance	How fine it filters	Best for
Cartridge	Moderate buy, pricier long-term (replace elements every 3–5 yrs)	Hands-on — no backwashing, you hose elements down	10–20 microns	Drought areas / water-discharge limits, average pools
Sand	Cheapest to buy and run (sand lasts 5–7 yrs)	Easiest — just turn a valve to backwash	20–40 microns	Heavy leaf load, algae-prone pools
D.E.	Most expensive	Hardest — backwash + add powder + annual grid teardown	1–5 microns (clearest water)	High-end pools wanting glass-clear water

Quick version: sand is the cheapest and easiest but coarsest. D.E. gives the clearest water but is the most work. Cartridge sits in the middle and saves water because you never backwash it.

The most common filter problems (and how to fix them)

1. Pressure gauge reading too high

The #1 filter complaint. High pressure means dirt has loaded up the media and is choking water flow. Rule of thumb: clean the filter when the gauge reads 10–12 PSI above the clean starting pressure you logged at install or last media change. Running it dirty wastes power and can crack the tank internals.

2. Leaking at the clamp band

On split-tank filters (Pentair Clean & Clear Plus, Jandy CV, Hayward SwimClear), the two halves seal with a big rubber O-ring under a tension clamp. Leaks mean the O-ring is flat, chemically degraded, or got pinched on reassembly. Clean the O-ring channel, lube it with silicone, and tighten the clamp evenly — tap it with a rubber mallet so the spring coils seat all the way around.

3. Sand blowing back into the pool

Means a cracked lateral — one of the slotted plastic tubes at the bottom of the sand tank. Usually from age or from dumping sand in without a water cushion during a refill. Once a lateral breaks, sand bypasses the bed and shoots out your return jets. Fix is replacing the broken laterals.

4. D.E. powder coming back into the pool

A milky pool after backwashing means a tear in a grid's filter cloth, a cracked top manifold, or a missing air-bleed strainer. The fine powder slips through the breach. Find the torn grid and replace it.

5. When to replace cartridges

Replace when the elements won't return to baseline pressure after a thorough cleaning, or when the pleats are matted, frayed, or the core is collapsing. Most last 3–5 years.

6. Air bubbles inside the filter / no flow

Bubbles or a pump running with no flow usually point to the suction side, not the filter — a clogged skimmer or impeller, or air being drawn in at the pump lid O-ring. Clear the baskets and reseal the pump lid.

7. Multi-port valve leaking to waste

On sand and some D.E. filters, water running out the waste line while filtering means the internal spider gasket in the multi-port valve has blown. Replace the gasket or the valve.

Find your filter: full model reference (2016–2026)

Brand	Model (Number)	Type	Area / Capacity	Flow (GPM)	Common problems	Status
Hayward	SwimClear (C2030–C7030, W3C3030, C3025)	Cartridge	225–700 sq ft	120–150	Broken clamp, hazy water from off-brand cartridges, air bleed fails	Current
Hayward	ProGrid (DE2420–DE7220)	D.E.	24–72 sq ft	48–144	Air relief assembly fails, D.E. blowback, high pressure	Current
Hayward	Pro Series (S180T–S244T)	Sand	150–300 lbs	20–160	Sand in pool, valve leaking to waste, stripped split-nut	Current
Jandy	CV / CL (CV340–580, CL340–580)	Cartridge	340–580 sq ft	127–150	Dirt return (torn cartridge), worn O-ring, high startup pressure	Legacy → CS/CV equivalents
Jandy	DEV (DEV48, DEV60)	D.E.	48–60 sq ft	96–150	Pressure locking the clamp, backwash O-ring leaks, manifold cracks	Current
Jandy	JS (JS60-SM, JS100-SM)	Sand	N/A	N/A	Valve gasket fails, gauge fails, broken laterals	Discontinued → SFTM series
Pentair	Clean & Clear Plus (CCP320–520, 160340)	Cartridge	320–520 sq ft	120–150	High pressure, broken tank clamp, air relief leak	Current
Pentair	Quad D.E. (Quad 60–100)	D.E.	60–100 sq ft	up to 160	Cartridge core collapse, media tearing, low flow	Current
Pentair	FNS Plus (FNSP24–60)	D.E.	24–60 sq ft	48–120	Clamp band dropping, torn curved grids, frequent backwash	Current
Pentair	Triton II (TR100 / EC-140210)	Sand	600 lbs	74	Trapped air pockets, drain blockages, bulkhead leaks	Current
Waterway	Crystal Water Cartridge (570-0325–0525)	Cartridge	325–525 sq ft	150	Stripped clamp nut, hard-to-remove clamp, pinched O-ring	Current
Waterway	Crystal Water D.E. (570-0036/0048/0060-07)	D.E.	36–60 sq ft	72–150	Grid bypassing debris, manifold cracks, heavy clamp	Current
Waterway	Carefree (FS02225, 16"/19"/22")	Sand	100–250 lbs	35–55	Top valve leak, sand blowback, split-nut failure	Current

Does a filter keep my pool from turning green?

No — and this trips up a lot of owners. A filter removes dead algae and debris, but it doesn't sanitize. A pool going green is a chemistry failure: not enough free chlorine, or cyanuric acid so high it locks up the chlorine you have. Fix the chemistry first; the filter clears the water once the chlorine kills the algae.

Frequently asked questions

Cartridge, sand, or D.E. — which pool filter is best?: Sand is cheapest to buy and easiest to maintain but filters coarsest (20-40 microns). D.E. gives the clearest water (1-5 microns) but is the most work. Cartridge is in between and saves water because it is never backwashed.
Why is my pool filter pressure so high?: Dirt has loaded the media and is choking flow. Clean the filter when the gauge reads 10-12 PSI above the clean baseline pressure. Running it dirty wastes power and can damage the tank.
Why is sand blowing back into my pool?: A lateral — a slotted tube at the bottom of the sand tank — has cracked, letting sand bypass the bed and shoot out the return jets. Replace the broken laterals.
Why is D.E. powder coming back into my pool?: A grid's filter cloth is torn, the top manifold is cracked, or an air-bleed strainer is missing, letting the fine powder through. Find and replace the torn grid.
When should I replace my filter cartridges?: When they won't return to baseline pressure after a thorough cleaning, or when the pleats are matted or the core is collapsing. Most cartridges last 3-5 years.
How do I safely open a pressurized pool filter?: Shut the pump off at the breaker and open the air-relief valve until the pressure gauge reads zero before loosening the clamp. A pressurized lid can separate with deadly force.
My pump runs but there's no water flow. Is it the filter?: Usually not — it's a suction-side problem like a clogged skimmer or impeller, or air drawn in at the pump lid O-ring. Clear the baskets and reseal the lid.
Will running my filter stop my pool from turning green?: No. A filter removes debris but doesn't sanitize. Green water is a chemistry failure — low free chlorine or high cyanuric acid. Fix the chemistry and the filter clears it up.

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Written by the PRNM team

Pool Rental Near Me is the peer-to-peer pool rental marketplace America loves — connecting pool owners with guests for hourly rentals across the US. Our editorial team works with hosts and licensed pool pros to keep these guides current.