Premium Quality. Trusted Brands. No Gimmicks.
Heater & Spa Parts supplies premium-grade pool and spa cartridge filters. Unless otherwise stated on the individual product listing, our replacement cartridges are supplied by leading filter manufacturers including Magnum® and Darlly®, using high-quality filtration media such as Reemay®, Darlly® media, Pleatco® media or equivalent premium-grade material.
Not sure which filter you need?
Use our Filter Finder to search by dimensions, model or cartridge number.
Magnum and Darlly are established specialist cartridge-filter manufacturers supplying replacement and OEM filtration products throughout the pool and spa industry. Major equipment and spa brands generally do not manufacture their own cartridge elements. Instead, cartridges are commonly produced by specialist filtration manufacturers to suit the required housing, dimensions and filtration specifications.
Their products are used across equipment from brands including AstralPool, Balboa, Davey, Emaux, Halo Spas, Hurlcon, Madimack, Oasis Spas, Sapphire Spas, SpaNet, Spa World, Vortex®, Waterco, Zodiac and many others.
Because we purchase filters in significant volumes, we can offer recognised premium filter brands at competitive pricing without relying on cheap, unidentified generic cartridges commonly found through marketplace sellers.
Why filter quality matters
A cartridge filter needs to maintain water flow while trapping fine debris without the media prematurely collapsing, separating or shedding fibres.
- Quality filtration media with consistent pleat construction
- Strong end caps and centre cores
- Better resistance to repeated cleaning cycles
- Reduced risk of premature fibre shedding or media failure
- Reliable filtration without unnecessarily restricting water flow
Cheap cartridges can look almost identical when new, but differences in media quality, pleat construction, bonding and internal support can significantly affect service life and filtration performance.
NSF® and recognised filtration materials
Many premium filtration materials and cartridge ranges from manufacturers such as Darlly®, Magnum®, Pleatco® and Reemay® are manufactured using materials tested or certified to recognised filtration and water-industry standards. Where a specific NSF® certification applies to a product, media or material, this should be considered in conjunction with the manufacturer's specifications for that particular cartridge.
How to clean a cartridge filter
Clean the cartridge when:
- Spas: water flow or jet pressure noticeably reduces.
- Pools: filter pressure rises approximately 35 to 45 kPa above the normal clean-filter pressure, unless the equipment manufacturer specifies otherwise.
Cleaning procedure:
- Switch the filtration system off and remove the cartridge according to the equipment manufacturer's instructions.
- Rinse loose debris from between the pleats using a garden hose.
- Periodically soak the cartridge in a purpose-made cartridge filter cleaning solution to remove oils, lotions and accumulated contamination.
- Rinse thoroughly after soaking.
- Reinstall the cartridge carefully and ensure all seals, lids and locking components are correctly seated.
Important:
- Do not use a pressure washer or high-pressure nozzle on cartridge media.
- Do not aggressively scrub the pleats with a hard brush.
- Avoid flocculants and excessive use of clarifiers with cartridge filters.
- Maintain correct water chemistry to maximise cartridge life.
When should a cartridge filter be replaced?
There is no single replacement interval that applies to every pool or spa. Cartridge life depends on water chemistry, operating hours, contamination, cleaning frequency and how heavily the system is used.
As a general guide, many cartridges are replaced approximately every 12 to 24 months, but replacement should be based primarily on condition and performance.
Replace the cartridge if you notice:
- Torn, frayed or separating filter media
- Cracked or damaged end caps
- Collapsed or badly distorted pleats
- Persistent poor flow even after proper cleaning
- Contamination or staining that cannot be removed
- The cartridge no longer returns to normal operating pressure after cleaning
Warranty
Unless otherwise stated, our standard cartridge filters are covered by a 12-month replacement warranty against manufacturing defects in materials or workmanship. Disposable cartridges and filters used in inflatable spas may have different warranty conditions. Damage caused by incorrect installation, misuse, excessive pressure, chemical damage, poor water chemistry or improper cleaning is not considered a manufacturing defect.
Why buy your filter from Heater & Spa Parts?
- Recognised filter manufacturers including Magnum® and Darlly®
- Premium Reemay®, Darlly®, Pleatco® or equivalent filtration media where specified
- Thousands of replacement applications across pool and spa equipment
- Competitive pricing through high-volume purchasing
- Dedicated online Filter Finder to help identify the correct cartridge
- Real pool and spa parts knowledge if you need help identifying an unusual filter
Buy the correct filter once. Match the dimensions, end configuration and cartridge number carefully before ordering, and use our Filter Finder if you are unsure.
