Grefilt C500 Pool Filter Cartridge 50 sq. ft. — 30‑Micron Trilobal Fabric, Reinforced End Caps

The Grefilt C500 is a 50 sq. ft. replacement pool filter cartridge with 30-micron trilobal fabric, NSF/ANSI 50 safety certification, and reinforced end caps for longer life.

Built to fit many common filter housings, the Grefilt C500 offers a high-capacity, heavy-duty replacement option for residential pools and spas. Its 5 oz trilobal filtration fabric and integrated support core deliver consistent particle capture while resisting premature collapse. The cartridge’s measured dimensions and 30-micron rating make it a straightforward swap for compatible models; always check your existing filter size and openings before ordering.

What materials and certifications does this cartridge use?

The C500 uses a 5 oz heavy-duty trilobal filtration fabric wrapped around a reinforced support core and finished with high-strength ABS end caps. It has been tested to NSF/ANSI 50 standards for materials safety in pool and spa equipment, ensuring the components are suitable for aquatic use.

• 5 oz trilobal fabric for increased fiber branching and capture
• ABS end caps and integrated support core for structural stability
• NSF/ANSI 50 tested materials for pool and spa compatibility

How fine is the filtration and what does 30-micron mean in practice?

With a 30-micron rating, the C500 captures relatively small suspended particles such as fine debris, some algae cells, and other common pool contaminants. The trilobal fiber structure increases surface area and branching to trap particles more effectively without dramatically restricting flow.

• 30-micron nominal filtration for fine particulate removal
• Trilobal fibers offer roughly 40% more branching for better retention
• Designed to balance capture efficiency with stable water flow

Will this cartridge fit my filter system and what are the key dimensions?

The Grefilt C500 is sized to work as a replacement for many popular cartridges—measure your existing filter to confirm compatibility. The cartridge length, outside diameter, and top/bottom opening dimensions are critical to ensuring a proper seal and fit in your housing.

• Overall length: 19 3/4 inches
• Outside diameter: 7 inches; top & bottom opening: 3 inches
• Filtration area: 50 sq. ft.; verify dimensions against your current cartridge

How durable is the C500 and what maintenance improvements can you expect?

Grefilt designed this cartridge for extended life using thicker media and reinforced components. The heavier fabric and support structure reduce the rate of media collapse and clogging, which can extend service intervals compared with thinner, lower-density cartridges.

• Thickened 5 oz fabric for increased longevity
• Integrated support core and strong end caps resist pressure wear
• Lower clogging tendency helps extend cleaning intervals

Who is this for: The Grefilt C500 is suitable for pool and spa owners who need a robust, NSF/ANSI 50-tested replacement cartridge with a 50 sq. ft. filtration area and 30-micron rating. It’s a good choice for households looking to upgrade from thinner media cartridges or for anyone replacing an original equipment cartridge that matches these dimensions. Check compatibility with your manufacturer references (Pleatco PA50-EC, Unicel C-7656, Filbur FC-1240 and similar) before purchase; manufacturer names are provided for reference only.