Unicel C-7479 | 75 sq ft Caldera Spa Filter Brand_Oreq Using a smartphone

Using a smartphone

Matching that fitting style matters more than matching square footage: a cartridge with the right filtration area but the wrong bottom connection won't seal

Each Serene bromine cartridge lasts 2–4 weeks

Stain & Scale Defense is preventive maintenance that costs less than fixing the damage it prevents

This cartridge uses a 2 inch SAE (buttress) thread

Unicel C-7479 | 75 sq ft Caldera Spa Filter Brand_Oreq Using a smartphoneThe Unicel C 7479 delivers 75 square feet of filtration across 216 pleats of Reemay 2033 polyester media. Built to meet or exceed OEM specifications, it's the replacement cartridge for Caldera Spas models using OEM part 033017. 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