POOLPURE Spa Cartridge Filter Replacement 2-Pack — Fits Unicel C-4326RA, Antimicrobial Trilobal Fabric, Longer Life

POOLPURE Antimicrobia PRB25-IN-M is a 2-pack replacement spa cartridge filter engineered to fit Unicel C-4326RA-style housings while resisting biofilm and microbial buildup.

This pair of replacement cartridges gives spa and hot tub owners a direct-fit option with certified performance and extended life. Each filter measures 13 5/16" long with a 5" outer diameter and 2 1/8" top and bottom openings, designed to slide into compatible systems without modification. Built from a trilobal fabric infused with antimicrobial materials, these cartridges aim to reduce biofilm accumulation and simplify maintenance for clearer water and more reliable system protection.

Will these replace my Unicel C-4326RA cartridges?

Yes — the PRB25-IN-M cartridges are made to match the critical dimensions of Unicel C-4326RA and other listed models for a straightforward swap. Measure your existing cartridge to confirm fit before purchasing.

• Length: 13 5/16"
• Outer diameter: 5"
• Top opening: 2 1/8"; Bottom opening: 2 1/8"
• Compatible references: PRB25-IN-M, Unicel C-4326RA, SD-00196, M-4326, and others

How does the antimicrobial fabric affect spa maintenance?

The filter media contains additives that help slow microbial and biofilm formation so contaminants are less likely to cling to the pleats. That means cleaner water between deep cleans and easier rinsing when you perform routine maintenance.

• Trilobal fabric releases debris more easily during rinsing
• Reduced biofilm accumulation improves system cleanliness
• Recommended cleaning interval: every two weeks for optimal performance

How long will these POOLPURE cartridges last compared with standard filters?

POOLPURE engineered these cartridges to last up to 30% longer than many standard replacements when cared for properly. With regular rinsing and periodic deep cleaning, a single cartridge can provide reliable service for two-plus years in typical residential spa use.

• Designed for up to 30% longer lifespan
• Performance restored quickly after washing
• Longevity depends on usage, water chemistry, and maintenance

Are these filters certified and trusted by industry groups?

Yes — the filters are tested against NSF/ANSI 50 standards and are produced by a brand active in industry organizations. PoolPure highlights partner relationships and independent testing to demonstrate suitability for demanding aquatic environments.

• IAPMO-tested to NSF/ANSI 50 standards
• POOLPURE is a member of the Pool & Hot Tub Alliance (PHTA)
• Field-tested in competitive settings and endorsed by athletic partners

Who is this for? If you own a spa or hot tub that accepts 13 5/16" x 5" cartridges with 2 1/8" openings and you want an easy-fit replacement that resists biofilm, simplifies cleaning, and can last longer than a basic cartridge, this two-pack is a practical choice. It appeals to homeowners focused on straightforward maintenance, facilities that demand consistent water quality, and anyone replacing Unicel C-4326RA-style filters without changing plumbing or housings.