Keep your spa water crystal clear with the ProAqua 4CH-35 Replacement Filter Cartridge, a premium replacement filter designed for select Sundance® and Hot Spring® spa models. Engineered to capture dirt, body oils, debris, and other contaminants, this high-performance cartridge helps maintain clean water while supporting efficient circulation and heater operation.
Manufactured with durable pleated filtration media, the 4CH-35 delivers reliable filtration performance and excellent water flow. Its threaded bottom connection and handle-top design allow for easy installation and removal, making routine spa maintenance simple and effective.
Key Features
✔ 35 square feet of filtration area
✔ Premium pleated filtration media
✔ Improves water clarity and cleanliness
✔ Captures dirt, oils, and contaminants
✔ OEM-quality replacement performance
✔ Handle-top design for easy removal
✔ 1-1/2" MPT threaded connection
✔ Durable construction for long filter life
Specifications
| Specification |
Details |
| Filter Area |
35 Sq. Ft. |
| Diameter |
4-5/8" |
| Length |
16" |
| Top Style |
Handle |
| Bottom Style |
1-1/2" Male Pipe Thread (MPT) |
| Media Type |
Premium Pleated Filtration Media |
| Filter Type |
Replacement Cartridge |
Compatible Spa Brands & Models
This filter is commonly used in:
Hot Spring Spas®
- Grandee (older models)
- Select Watkins® Hot Spring spa models
- Various Hot Spring filtration systems utilizing the PTL35 / 4CH-35 filter configuration
Sundance Spas®
- Sundance models using OEM filter 6540-486
- Select Sundance spa filtration systems requiring the 4CH-35 cartridge
Additional Compatible Applications
- Watkins® Spa Systems
- Select legacy spa systems using a 35 sq. ft. threaded filter cartridge
Always verify dimensions and thread style before ordering.
Cross Reference Part Numbers
This filter is compatible with and replaces:
- ProAqua 40351
- Darlly 40351
- Unicel 4CH-35
- Pleatco PTL35P
- Pleatco PTL35P4
- Filbur FC-0161
- Sundance 6540-486
- Baleen AK-9006
- Watkins 31382
- SD-00007
Why Replace Your Hot Tub Filter?
Regular filter replacement helps:
- Improve water clarity
- Increase filtration efficiency
- Reduce strain on pumps and heaters
- Improve sanitizer effectiveness
- Extend spa equipment life
- Maintain proper water circulation
For best results, rinse your filter every 2 to 4 weeks and perform a deep cleaning every 3 to 4 months. Replace the cartridge every 12 months, or sooner for heavily used spas.
Pro Tip
Keep a second filter cartridge on hand and rotate filters during cleaning. Allowing a cleaned cartridge to dry completely between uses can help improve filtration efficiency and extend filter lifespan.
