Unicel C-8380 | 80 sq ft Sundance MicroClean Filter

By Unicel
SKU: C-8380
$87.99

Let's Ensure This Fits Your Model

Check out the Filter Guide to see if this filter fits your hot tub model.

If you have questions, call us at (208) 973-1384 or send us an email to hello@leisuretimeinc.com

If possible, please have your hot tub’s serial number ready when you contact our team.

Check Discount Eligibility
Low stock

Pickup available at Leisure Time Inc. - Idaho Falls

Usually ready in 24 hours

View store information

Description

The Unicel C-8380 is the 80 square foot pleated cartridge for the Sundance Spas MicroClean filtration system — the large-diameter workhorse that handles the bulk of what your spa water carries. It replaces Sundance part number 6540-501 and is built to meet or exceed the factory cartridge specification.

Read this part before you order: MicroClean is a two-piece system, and the C-8380 is one of the two pieces. It replaces the pleated cartridge only. The second component — the MicroClean disposable microfiber cartridge, Sundance part number 6540-502 — threads onto the top of this one and is sold separately. If your existing microfiber cartridge is discolored, collapsed, or simply old, you need both. Ordering this cartridge alone when the microfiber is also spent leaves you with an incomplete assembly and water that never quite clears up.

Once you understand why Sundance split filtration into two stages, the design makes sense. A single cartridge always forces a compromise: media fine enough to catch the microscopic particles that cause haze will clog almost immediately on hair and leaves, while media open enough to survive bulk debris lets the fine stuff straight through. MicroClean sidesteps the compromise by assigning each job to purpose-built media. This cartridge, with 174 pleats across 80 square feet, has the capacity and the durability to absorb the heavy organic load — body oils, lotion, sweat, hair, leaves, and grit — season after season, and it is fully cleanable. The microfiber stage above it captures the fine particulate that would otherwise pass straight through, and it is disposable by design.

Construction is standard Unicel: 3 oz Reemay polyester media over a solid injection-molded core, with chemical-resistant end caps molded to an exact OEM fit — a closed top carrying a 2" SAE thread for the microfiber cartridge, and an open 2-1/2" beveled bottom that seats into the filter canister. Made in the USA by Meissner Manufacturing, with more than 45 years behind the Unicel name.

Pro Tip: The two stages wear out on different schedules, and matching your buying to that is where MicroClean owners save real money. The disposable microfiber cartridge is the consumable — it loads with fine particulate and generally needs replacing several times over the life of one pleated cartridge. This pleated cartridge is the durable half: rinse it, deep-soak it, and it keeps performing far longer. Replacing both every time is money wasted, and replacing neither is the reason a spa slowly goes cloudy without any obvious cause. Inspect both at every drain and refill, and replace each one on its own merits.

Brand

UNICEL®

Key Features
  • 80 square feet of filtration area: Substantial capacity built to absorb the heavy organic load in a Sundance spa, so flow stays steady far longer between cleanings.
  • 174 pleats: Uniform folds across a large 8-7/16" diameter, spaced widely enough that trapped debris rinses free rather than packing permanently into the media.
  • Purpose-built for the MicroClean two-stage system: Handles bulk debris so the microfiber stage above it is free to do the fine work it was designed for.
  • Closed top with 2" SAE thread: The precise mating point for the MicroClean disposable cartridge, machined to seat cleanly and hold under sustained suction.
  • Open 2-1/2" beveled bottom: The beveled edge guides the cartridge into correct alignment as it seats and helps form a proper seal against the canister base.
  • 3 oz Reemay polyester media: One hundred percent polyester with strong chemical resistance, balancing dirt-holding capacity against cleanability so the cartridge recovers well through repeated wash cycles.
  • Fully cleanable and reusable: Unlike the disposable microfiber stage, this cartridge is designed to be rinsed and deep-soaked repeatedly across a long service life.
  • Solid injection-molded core: Holds pleat geometry and structural alignment under the load of a large-diameter cartridge.
  • Made in the USA: Manufactured by Meissner Manufacturing to meet or exceed OEM specification.
How It Works

The C-8380 seats into the filter canister with its open beveled bottom over the suction fitting, and the MicroClean microfiber cartridge threads onto the 2" SAE fitting at its closed top. Together the two form a single sealed column. When the circulation pump runs, it draws water out through the bottom opening, creating lower pressure inside the shared core than in the surrounding spa water.

That pressure difference pulls water inward through both stages at once. Spa water passes through this cartridge's pleated polyester from every direction across its full 8-7/16" circumference, and simultaneously through the microfiber media above. Both feed the same central core, and the combined filtered flow exits the beveled bottom into the suction plumbing. Two very different media types work in parallel on the same body of water — the pleated stage taking the volume and the bulk, the microfiber stage polishing out what the pleats let pass.

The closed top end cap is what makes this arrangement possible. On a conventional cartridge, both ends are open and water exits either way. Here, sealing the top forces the connection to run through the threaded fitting into the microfiber cartridge instead. That is also why this cartridge cannot substitute for a standard open-ended filter, and why a standard filter cannot substitute for it — the flow path is fundamentally different.

Debris loads into the depth of the polyester fibers rather than sitting on the surface, which is why a cartridge that still looks reasonably clean can already be meaningfully restricted. On a spa this size, declining jet pressure is the most reliable early signal that a cleaning is due.

Pro Tip: The closed top changes how you rinse this cartridge. On an open-ended filter you can flush debris outward by running water down through the core — that does not work here, because the top is sealed. Instead, work strictly from the outside in: hold the cartridge at an angle with the open bottom pointing down so gravity carries loosened debris out and away, and spray downward into the pleats while rotating slowly through the full circumference. Rinsing with the open end pointing up simply washes debris into the core, where it stays until it gets pulled back into your plumbing.

Directions for Use

Installation

  1. Turn the spa off at the breaker before opening the filter compartment.
  2. Remove the filter lid and lift out the complete assembly — pleated cartridge and microfiber cartridge together.
  3. Unthread the MicroClean microfiber cartridge from the top of the old pleated cartridge by turning counterclockwise. Inspect it and set it aside if it is still serviceable, or replace it if it is spent.
  4. Inspect the canister and suction fitting. Clear away hair, grit, and debris that have collected in the well.
  5. Thread the microfiber cartridge onto the 2" SAE fitting at the top of the new C-8380. Tighten by hand only — never use a tool on a molded plastic thread.
  6. Lower the completed assembly into the canister, seating the beveled bottom over the suction fitting. Confirm it sits square and does not rock or lean.
  7. Replace the lid, restore power at the breaker, and run a full circulation cycle.
  8. Verify normal jet pressure and flow. A clear improvement over the old assembly is expected.

Routine Cleaning

  • Every 2 to 4 weeks: Separate the two cartridges and rinse this pleated cartridge with a garden hose, working from the outside in with the open bottom pointing down. Rotate steadily so every pleat gets direct attention.
  • Every 3 months: Deep-soak the pleated cartridge in a dedicated spa filter cleaning solution to dissolve body oils, lotion residue, and mineral scale that rinsing cannot remove. Rinse thoroughly afterward — cleaner left in the media is a common and entirely preventable cause of foaming.
  • Do not soak or scrub the microfiber cartridge. It is disposable by design and chemical cleaning damages the media. Rinse it gently if the manufacturer's instructions allow, and otherwise replace it on schedule.
  • At every drain and refill: Deep-clean the pleated cartridge and inspect the microfiber cartridge before either goes back into fresh water.
  • Rotate two pleated cartridges if you can: Keeping a spare lets you install the clean one immediately while the other dries completely. A fully dried cartridge releases trapped debris far more easily on the next rinse, and rotating roughly doubles the useful life of both.

Important Cautions

  • Do not use a pressure washer. High-pressure spray tears media fibers and destroys pleat geometry, often without visible damage, and torn media passes unfiltered water straight through.
  • Do not use a wrench, pliers, or any tool on the 2" SAE threaded fitting. Hand-tight is correct, and overtightening cracks the end cap.
  • Do not clean with dish soap, laundry detergent, or household cleaners. These leave residues that foam persistently and are difficult to rinse out.
  • Do not run the spa with the pleated cartridge alone or with the microfiber cartridge alone. The assembly is designed to run complete, and running it partial leaves an unfiltered path into your plumbing.
  • Do not run the spa with no cartridge at all, even briefly. Debris pulled directly into the pump causes damage costing far more than a filter.
  • Do not boil, bleach, or machine-wash either cartridge.

When to Replace

Replace this pleated cartridge when you see torn or separated media, cracked or deformed end caps, damaged or stripped threads on the top fitting, a soft or collapsing core, pleats that have permanently lost their shape, staining that no longer responds to a deep soak, or a persistent drop in flow that thorough cleaning no longer restores. Thread damage warrants immediate replacement regardless of media condition — if the microfiber cartridge cannot seat and seal properly, the two-stage system stops working as designed. Most Sundance owners under typical use replace the pleated cartridge every 12 to 18 months, and the microfiber cartridge considerably more often.

Specifications
  • Brand: Unicel
  • Manufacturer: Meissner Manufacturing Co., Inc.
  • Part Number: C-8380
  • Product Type: Replacement spa filter cartridge, pleated stage for two-piece MicroClean assembly
  • Filtration Area: 80 sq. ft.
  • Pleat Count: 174
  • Filter Media: 3 oz. Reemay polyester
  • Outer Diameter: 8-7/16"
  • Length: 14"
  • Top End Cap: Closed, with 2" SAE thread
  • Bottom End Cap: Open, 2-1/2" inner diameter, beveled edge
  • Core: Solid injection-molded, full-length
  • End Cap Material: Chemical-resistant molded plastic, exact OEM fit
  • Replaces OEM: Sundance Spas 6540-501 (pleated cartridge only)
  • Cross-References: Pleatco PSD85-2002, Filbur FC-2810, Aladdin 18007, Baleen AK-70031, Darlly 80801, Magnum SU80
  • Companion Component Required: MicroClean disposable microfiber cartridge, Sundance 6540-502 / Filbur FC-2812 — sold separately
  • Quantity Per Spa: One complete assembly, consisting of one pleated cartridge and one microfiber cartridge
  • Typical Service Life: 12 to 18 months with routine cleaning
  • Cleaning Method: Hose rinse every 2 to 4 weeks; chemical soak every 3 months. Do not pressure wash.
  • Installation: Hand-tighten the threaded fitting only. Do not use tools.
  • Not Compatible With: Sundance models using a conventional single open-ended cartridge rather than MicroClean
  • Origin: Made in the USA
  • Shipping: Standard ground; not classified as a hazardous material
Compatibility

Replaces This OEM Part Number

  • Sundance Spas 6540-501 — the pleated cartridge only

Cross-Reference Part Numbers

  • Pleatco PSD85-2002
  • Filbur FC-2810 (antimicrobial version listed as FC-2810M)
  • Aladdin 18007
  • Baleen AK-70031
  • Darlly 80801
  • Magnum SU80

Spa Brands Using This Cartridge

  • Sundance Spas equipped with the MicroClean filtration system
  • Sweetwater Spas
  • Morgan Spas

The Companion Cartridge You May Also Need

The MicroClean disposable microfiber cartridge — Sundance part number 6540-502, also sold under the Filbur designation FC-2812 — threads onto the top of this cartridge and completes the assembly. It is a separate purchase. If you are unsure whether yours needs replacing, pull it and look: microfiber that has gone gray or brown, feels stiff, or has begun to separate or collapse is finished, and no amount of cleaning will bring it back. Unlike the pleated cartridge, it is not designed to be soaked or scrubbed.

How to Confirm Fitment

Square footage alone is not a fitment match. Verify all four against your existing cartridge before ordering:

  • Top end cap: Closed, with a 2" SAE thread. This is the single most distinctive identifying feature — if your cartridge has an open top or a handle, it is not this filter.
  • Bottom end cap: Open, 2-1/2" inner diameter, with a beveled edge.
  • Outer diameter: 8-7/16".
  • Overall length: 14", measured end cap to end cap and excluding the threaded fitting.

Pro Tip: Match by the part number printed on the end cap of your existing cartridge, not by spa model year. Sundance changed filtration specifications across production runs, and two spas of the same model and year can take different assemblies — some Sundance models use a conventional single cartridge rather than MicroClean at all. If the label on your old filter has worn off, the closed top with the 2" SAE thread is the giveaway: no conventional spa cartridge has one. Our team can also confirm the correct assembly from your spa's serial number, which is the surest route if you are replacing both stages at once.

Most products purchased from our online shop within the last 30 days are eligible for return. Please review our return policy to see the list of items that cannot be returned.

Some major items that are non-returnable:

  • Gift cards
  • Electronics
  • Pumps / Motors
  • Hot Tubs
  • Closeouts
  • Fireplaces
  • Electric Fireplaces
  • Massage Chairs
  • See return policy below for full list of non-returnables.

UNICEL® Brand FAQs

Who makes Unicel filters?

Unicel filters are made byMeissner Mfg. Co., Inc., a family business that began as a small contract sewing operation in thelate 1950sand moved into pool filtration through the 1970s. By the end of that decade the company was producing cartridge filters for the industry'soriginal equipment manufacturers, and in1985it introduced the Unicel brand as aftermarket replacements. It's still owned and operated by the Meissner family today.

Are Unicel filters as good as the original manufacturer's filter?

Unicel builds its cartridges tomeet or exceed original equipment specifications— and that's a meaningful distinction here, because the company produced cartridges for the industry's OEMs before it ever launched its own brand. Unicel cartridges usedurable, chemical-resistant end capswith an exact fit,high-capacity media,uniform pleatsfor optimal flow, and asolid corethat resists collapsing under pressure.

Where are Unicel filters made?

Unicel filters are manufactured inCalifornia, with components sourcedexclusively in the United States. The line comprisesnearly 500 products, covering replacement cartridges, D.E. grids, filter discs, and related parts.

How do I find the right Unicel filter for my spa?

Unicel cartridges areinterchangeable with all major filter brands, and each one cross-references to a list of original equipment part numbers. The most reliable method is topull your current cartridge and read the part number printed on it, then match it to the Unicel cross-reference. If the number has worn off,measure your old cartridge— diameter, length, and the size and style of the openings at each end — and match those instead. Also confirmhow many cartridgesyour spa uses.

How long does a Unicel filter last?

Cartridge life depends on how heavily the spa is used, yourwater chemistry, and how consistently you clean the filter. Many Unicel cartridges useReemay® polyester media, whosetrilobal fibersprovide considerably more surface area than standard rounded fibers — which increases dirt-holding capacity and extends the time between cleanings. With regular rinsing and periodic deep cleaning, a well-maintained cartridge commonly serves a year or more.

When should I replace my filter instead of cleaning it?

Replace the cartridge when thecycle between cleanings becomes noticeably shorter, when you seelow water flowor high differential pressure, when the media has atear, or if thecenter core collapses. Pleats that stay permanently flattened or discolored after a proper cleaning are another sign the cartridge has reached the end of its service life.

About UNICEL®

Unicel is the nation's leading manufacturer of replacement filter cartridges for pools and spas — and the story behind it is a genuinely American one. In the late 1950s, Richard T. Meissner started a small part-time contract sewing operation. Through the 1970s, Meissner Mfg. Co., Inc. moved into swimming pool filter bags, then D.E. grid element covering, and by the end of that decade the company was producing cartridge filters for the industry's original equipment manufacturers.

That's the detail that matters most: Unicel was building the filters that went into new spas long before it sold a replacement. In 1985, the company introduced the UNICEL brand so dealers and technicians could source elements built to O.E.M. specifications from a single place — even for equipment brands they didn't carry. Today the line spans nearly 500 products, all manufactured in California with components sourced exclusively in the USA.

By staying focused on one thing — filtration — Unicel has built deep expertise in a critical corner of the industry, from media development to cartridge design. Every cartridge is built with chemical-resistant end caps for an exact fit, high-capacity filter media, uniform pleats for optimal flow, and a solid core that holds its shape under pressure. Meissner Mfg. Co., Inc. remains owned and operated by the Meissner family, still recognized for quality and service. American-made products, world-class service.