Unicel C-4950 50 sq ft Spa Filter Cartridge 2-Pack - Clear Water Fit

Our review of the Unicel C-4950 replacement filter cartridges finds them best for hot tub and small pool owners who want reliable, no-frills filtration that keeps water clear without fuss. The two-pack supplies 50 sq ft of 3-ounce Reemay media per cartridge with 212 pleats, designed to trap particles down to about 20 microns. For anyone who values easy fitment, durability against chemicals, and straightforward maintenance, this cartridge delivers consistent performance and good value compared with single replacements.

Key Features

• 50 square feet media: Provides ample surface area to capture dirt and debris, reducing how often you need to clean the cartridge.
• 212 pleats, sharp folds: Uniform pleat folds maximize water flow and minimize pressure loss so the filter can hold more debris without choking the pump.
• 3-ounce polyester Reemay media: Balances dirt-holding capacity and cleanability while resisting common pool chemicals for longer life.
• Open end cap with 2-1/8 in ID: Simple open configuration and durable plastic construction make cartridge removal and replacement quick and reliable.
• Compatibility: Sized to fit many spa and pool brands, offering a broad fitment range for owners of popular hot tub systems.

Who It's For

This cartridge is ideal for owners of hot tubs and small pools using compatible cartridges who want an affordable, easy-to-maintain replacement. It suits people who perform routine cleaning and chemical maintenance and need a cartridge that tolerates those chemicals while maintaining clarity.

It is less suited to operators seeking specialty media for ultra-fine filtration beyond 20 microns or custom filter shapes; anyone requiring a different pleat count, nonstandard end cap, or specialty high-efficiency material should look for an alternative model matched to that need.

Pros & Cons

Pros

• High effective surface area from 50 sq ft and 212 pleats for sustained debris capture.
• Durable 100-percent polyester Reemay media resists pool chemicals and cleans up well.
• Open end cap with 2-1/8 in ID makes replacement and removal straightforward.

Cons

• Filtration rating around 20 microns is good for general use but not the finest available for specialty filtration needs.

Specifications

Model	C-4950 (pack of 2)
Media area	50 sq ft per cartridge
Pleat count	212 pleats
Media material	100% polyester Reemay, 3-ounce basis weight
Filtration size	Average 20 microns
End cap	Open configuration, 2-1/8 in ID
Dimensions	OD 4-15/16 in, Length 13-5/16 in

Our Verdict

The Unicel C-4950 2-pack is a practical, cost-conscious choice for hot tub and small pool owners who need reliable, chemical-resistant cartridges that fit popular systems. It balances surface area, cleanability, and durability, offering clear water performance and straightforward maintenance without premium cost.

Frequently Asked Questions

Will this cartridge fit my spa?
It fits many common spa and pool brands with an open end cap and 2-1/8 in ID, but check your current cartridge dimensions (OD 4-15/16 in, length 13-5/16 in) to confirm.

How fine is the filtration?
The media captures particles down to an average of about 20 microns, suitable for general debris and clarity maintenance.

Can these filters be cleaned and reused?
Yes, the 100% polyester Reemay media is designed for cleanability and chemical resistance, extending usable life with routine rinsing and care.