Unicel C-8327 | 125 sq ft Sundance Spa Filter

The Unicel C-8327 is a 125 square foot replacement cartridge for Sundance and Sweetwater spas, replacing OEM part number 6540-488. It is the largest cartridge in the Unicel spa range — 19" tall, 8-7/16" across, carrying 199 pleats — and it is the filter Sundance uses across an unusually wide span of its lineup, from the 850 Series of the early 2000s right through to current 980 Series spas. One hundred and twenty-five square feet is a serious amount of filtration, and the practical effect is worth understanding. Capacity does not make a filter clean better on any given pass. It determines how long the filter keeps performing before accumulated debris begins choking flow. Spread the same bather load across 125 square feet instead of 65, and the cartridge clogs at roughly half the rate, holds jet pressure steady far longer between cleanings, and asks considerably less of a circulation pump that would otherwise be straining against progressively tighter media. The cartridge connects at both ends, which is unusual and worth knowing before you install it. The top carries a 1-1/2" male slip fitting — a smooth, unthreaded collar that seals by close tolerance against a matching socket, the same principle as a PVC slip joint. The bottom is an open 2-1/2" end with a beveled edge that seats down over the fitting in the filter well, the bevel guiding the cartridge into alignment as it goes. Because there is a connection at each end, this cartridge has to engage correctly in two places rather than one. Media is 3 oz Reemay 2033 — one hundred percent spunbonded polyester over a solid injection-molded core, with chemical-resistant end caps built to an exact OEM fit. Made in the USA by Meissner Manufacturing, with more than 45 years behind the Unicel name. An antimicrobial version of this same cartridge is also produced, with blue treated media that inhibits odor-causing bacteria on the filter itself. Pro Tip — this cartridge may replace a two-piece filter assembly with a single part. Some Sundance spas use a two-component MicroClean setup: a pleated cartridge with a separate disposable microfiber cartridge threaded onto it, sold and replaced as two items. This 125 square foot cartridge is widely specified by filter manufacturers as a single-cartridge substitute for that two-part assembly — one purchase instead of two, with no microfiber cartridge to track separately. It is a genuinely appealing simplification if your spa accepts it. Verify before you switch: not every MicroClean housing takes this cartridge, and the two are not physically interchangeable in every case. Give us your spa's serial number and we will confirm which filter your housing is built for. Brand UNICEL®