Caldera Spas hot tub filters
The Unicel 2026 Replacement Guide lists 8 of the cartridges on this site for Caldera Spas. Many tubs use only one of these, so measure your old filter or check the number printed on its end cap.
| Cartridge (Pleatco / Unicel / Filbur) | Diameter × length | Sq ft | Models | Caldera Spas OEM # | Source |
|---|---|---|---|---|---|
| PRB35-IN / C-4335 / FC-2385 | 5" x 9-1/4" | 35 | not specified | 74148 | Unicel p.30 |
| PCD50 / C-7451 / FC-3084 | 7" x 10-3/4" | 50 | not specified | 033016 | Unicel p.30 |
| PCD50N / C-7350 / FC-3963 | 7" x 10-3/4" | 50 | not specified | 1019401, 73532 | Unicel p.30 |
| PRB50-IN / C-4950 / FC-2390 | 5" x 13-5/16" | 50 | not specified | 302005, 73533, 76076 | Unicel p.30 |
| PWK65 / C-8465 / FC-3960 | 8-1/2" x 10-1/2" | 65 | not specified | 76136 | Unicel p.30 |
| PCD75 / C-7479 / FC-3085 | 7" x 14-7/8" | 75 | not specified | 033017 | Unicel p.30 |
| PCD75N / C-7375 / FC-3964 | 7" x 14-7/8" | 75 | not specified | 1019301 | Unicel p.30 |
| PCD100W / C-8399 / FC-3965 | 8" x 16-1/2" | 100 | not specified | 1039607, 73722 | Unicel p.30 |
If your Caldera Spas filter isn't here, it may not be in our checked list yet. We only publish matches we can confirm in a manufacturer catalog.