Upper & Lower Spa Filter Cartridges - Sapphire, Signature & Others - Top & Bottom
Product is backordered and will ship as soon as it is back in stock.
Don't Guess - Ask Us!
Don't Guess - Ask Us!
Not sure if it’s the right part? Send us a message and a photo of what you’re replacing, or what you need, and we’ll help make sure you get the right part the first time.
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Upper & Lower Spa Filter Cartridges - Sapphire, Signature &...
Product is backordered and will ship as soon as it is back in stock.
Upper & Lower Swim Spa Filter Cartridge Pair to Suit Sapphire, Signature, Bullfrog & Other Widemouth Front Access Skim Filters
Premium upper and lower replacement filter cartridge pair for many swim spas and large spas using stacked widemouth front access skim filters. Commonly found on selected Sapphire, Signature, Spa Industries, Bullfrog, V-Stream, and other brands using this upper/lower cartridge style.
We also stock the Microban version of this upper and lower filter pair.
We keep these physically in stock, unlike drop-shipping websites. Fast shipping and local pick-up available.
This filter set uses a stacked top and bottom cartridge design. The upper filter has a closed top with handle and a smooth lower spigot that fits into the lower cartridge. The lower filter has an open crown top and a coarse ACME-style threaded spigot on the bottom. This style is commonly used in Waterway front access skim filter housings and similar wide mouth systems. :contentReference[oaicite:1]{index=1}
Common Part Numbers / Cross References
- SS50T - upper cartridge
- SS50B - lower cartridge
- FC-SS50T
- FC-SS50B
- SG100
- RFIL15050M
- RFIL15050F
- AFILK25MFS
- MSG100-K
- Unicel 6CH-942
Commonly Suits
- Sapphire swim spas and portable spas using stacked widemouth filters
- Signature spas using this upper / lower filter pair
- Spa Industries swim spas using this filter style
- Bullfrog swim spas using the widemouth stacked cartridge arrangement
- Waterway front access skim filter housings
- Selected V-Stream and other re-branded systems using the same dimensions and end configuration
Specifications / Dimensions
- Sold As: 1 x upper filter + 1 x lower filter
- Combined Height: approx. 425mm or 460mm overall, depending on version, excluding handle and threaded spigot
- Upper Filter: approx. 210 to 225mm height x 145 to 150mm outside diameter x closed top x 44 to 53mm smooth lower spigot
- Lower Filter: approx. 220 to 225mm height including crown x 145 to 150mm outside diameter x open crown top at approx. 44mm ID x 47 to 50mm coarse threaded lower spigot
- Top / Bottom Design: upper locks or slips into lower depending on version
100 sqft and 200 sqft Skim Filter Applications
These cartridges are commonly used in front access skim filter housings with two stacked cartridges. In many systems, one pair is used for 100 sq ft housings and two pairs are used for 200 sq ft wide mouth housings. :contentReference[oaicite:2]{index=2}
Quality Matters
These are not cheap low-grade marketplace filters. They are quality replacement cartridges made using USA-made Reemay or Darlly filter media for reliable water flow, solid dirt-holding capacity, and consistent performance. Cheap filters often use poorer media, fewer pleats, and weaker end caps, which can reduce cleaning performance and service life.
Important Before Ordering
- Please compare the photos, measurements, top style, and bottom connection carefully before ordering.
- The male / female spigot connection is intentionally a tight fit. If needed, warming the parts slightly can help them fit together properly.
- Some newer versions are slightly shorter overall but use more pleats to maintain similar filtration area. :contentReference[oaicite:3]{index=3}
- Many spas use similar-looking filters, so fitment should always be confirmed by dimensions and end style, not by spa brand alone.
Premium Quality. Trusted Brands. No Gimmicks.
Heater & Spa Parts only supplies premium-grade cartridge filters. Unless otherwise stated, our filters are Magnum® or Darlly® branded, made using USA-made Reemay®, Darlly®, Pleatco® filter media or equivalent. These two companies are among the biggest OEM suppliers to major spa and pool manufacturers, including Astralpool and many others.
Because we buy in container-load volumes, we can offer premium filters at sharper pricing and pass that value on to you.
Our filters are trusted across the industry, including by brands such as Astralpool, Balboa, Davey, Emaux, Halo Spas, Hurlcon, Madimack, Oasis Spas, Sapphire Spas, Spa World, Vortex®, SpaNet, Waterco, Zodiac, and more.
FYI, Most major manufacturers do not make cartridge elements themselves. They are supplied by OEM specialists like Magnum and Darlly, using Reemay or Darlly material, which are the same brands we supply.
These are not the cheap, unknown generics commonly sold on eBay, Wish, Temu, Amazon, and others. They are the same type of filters used by top manufacturers.
NSF® certified materials
All our filters are made from NSF® certified materials, meeting international standards for safety, strength, and filtration performance. Brands like Darlly®, Magnum®, Pleatco®, and Reemay® are globally recognised for consistent quality.
Why we mostly use Darlly® and Magnum®
Darlly® and Magnum® filters (with Reemay® or equivalent media) are chosen for real-world reliability:
- Stronger, continuous fibres for minimal shedding
- Greater durability compared to low-grade alternatives
- Longer service life and fewer replacements
- Cleaner, healthier water
Low-quality filters can shed fibres that clog or damage equipment. Ours are engineered to reduce shedding and keep your system running clean and efficient.
Filter cleaning guide
Clean your filter when:
- Spas: water flow or jet pressure drops
- Pools: filter pressure is about 35-45 kPa above normal
How to clean:
- Remove the cartridge as per your manufacturer’s instructions.
- Soak in a proper filter cleaning solution (for example Zodiac Filter Soak or Filter Klenz).
- Rinse thoroughly with a garden hose. A pleat-cleaning nozzle helps.
- Reinstall carefully and check seals are seated correctly.
Maximise filter life:
- Maintain balanced water chemistry.
- Clean regularly based on usage.
- Do not scrub with hard brushes or use high-pressure hoses.
- Avoid flocculants and avoid overusing clarifiers.
- Rotate multiple cartridges where possible to extend lifespan.
When to replace your filter
We recommend replacing cartridge filters every 12 to 24 months, depending on usage and conditions. Keeping a spare on hand allows easy rotation and uninterrupted filtration.
Warranty information
All standard filters are covered by a 12-month replacement warranty (excluding disposable and inflatable-spa types). This covers defects in materials or workmanship, not damage caused by improper use or poor water chemistry. See examples and warranty terms on our warranty page.
Summary: why choose our filters
- NSF® certified materials for proven safety and performance
- Trusted by major brands across the industry
- Mostly Magnum® or Darlly® branded filters, using Reemay® media or equivalent
- No gimmicks, just reliable, proven filtration
- Premium quality at sharp pricing through container-volume purchasing
Your spa or pool deserves more than a “just good enough” filter. Choose proven quality, backed by trusted names and genuine product knowledge.
Measuring a cartridge filter element when you dont have the exact model is the best way to identify it. There are a few important measurements, and they need to be as accurate as possible.
Total Length: Length of the filter, excluding the handle. You can generally also exclude the spigot or thread.
Diameter: This is the width of the filter.
Spigot Diameter: You may have a male threaded, or non-threaded spigot to locate the filter.
Hole Diameter: If you have a hole, rather than a spigot, measure the diameter of the hole.
Thread / Hole Type: Generally these can be a hole, a fine thread, course thread, or camlock style fitting.
SS50T + SS50B
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