The Unicel C-8465 delivers 65 square feet of filtration across 234 uniform pleats, capturing debris and particles down to an average of 20 microns. Built to meet or exceed OEM specifications, it's a direct replacement for a wide range of Hot Spring, Caldera, and Tiger River cartridges. 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 separates a Unicel from a bargain cartridge is what it's built from. The media is Reemay® polyester — a spunbonded, trilobal fiber whose three-lobed shape presents substantially more surface area than standard rounded fibers, balancing dirt-holding capacity, cleanability, and chemical resistance. Add sharp, uniform pleat folds that maximize flow and minimize pressure loss, 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 through cleaning after cleaning. Made in the USA. Pro Tip: Twenty microns is finer than you can see. A human hair is roughly 70 microns across, so this cartridge is capturing particles several times smaller than anything visible to the naked eye. That's exactly why water can look clear and still benefit from a fresh filter — the difference between "clear" and genuinely polished water happens at a scale you'll never spot by looking. Brand UNICEL®
