The Unicel C-6430 delivers 30 square feet of filtration across 124 pleats of heavyweight 4 oz Reemay® polyester media. Built to meet or exceed OEM specifications, it’s a direct replacement for the Hot Spring and Watkins cartridges used across a wide range of spas.
Filtration is the quiet backbone of clean spa water. Every soak leaves behind body oils, lotions, hair, and fine debris, and the cartridge is what removes all of it before it clouds the water, feeds bacteria, or coats your plumbing. When a filter is worn or clogged, the effects spread everywhere: dull water, higher chemical use, softer jets, and a pump and heater straining against restricted flow.
What sets this cartridge apart is the heavier media. Where most spa cartridges use a 3 oz fabric, the C-6430 is built with 4 oz Reemay — a denser, more substantial material that stands up better to repeated cleanings and resists the matting that shortens a filter’s life. Its trilobal fibers, three-lobed rather than round, pack substantially more surface area into the same material, balancing dirt-holding capacity with cleanability. Add chemical-resistant end caps with an exact OEM fit and a solid core that holds its shape under pressure, and you get a cartridge that performs season after season. Made in the USA.
Pro Tip: Check how many cartridges your spa uses before you order. Spas built around this 30 square foot size very often run a set of two or three rather than a single filter, and they should always be replaced together. Pairing one new cartridge with older ones leaves the fresh filter doing more than its share and gives you uneven filtration across the set.
Brand
UNICEL®
