Caldera Oasis Replacement Filter
6-person hot tub · 2002-2009 · 1 filter cartridge
Compatible Filter Cartridges
50 sq ft · 5″ OD × 13.3125″ long
| Pleatco | PRB50-IN |
| Unicel | C-4950 |
| Filbur | FC-2390 |
| OEM | Jacuzzi 373045 |
| OEM | Jacuzzi 373045J |
Frequently Asked Questions
What filter cartridge does the Caldera Oasis use?
The Caldera Oasis uses the PRB50-IN filter cartridge (also sold as C-4950). Always check the label inside your filter compartment or owner manual to confirm before ordering - part numbers are also printed on the end cap of the existing cartridge.
How many filters does the Caldera Oasis need?
The Caldera Oasis uses a single filter cartridge. Confirm by checking the filter housing in your spa - some models in the same series use two cartridges, so it's worth verifying against your specific serial number if you're unsure.
How often should I replace the filter on my Caldera Oasis?
Most Caldera owners replace filter cartridges every 12-24 months, or sooner if water clarity declines despite regular cleaning. Rinse the cartridge monthly by spraying between the pleats at a 45-degree angle, and deep-clean it every 3-4 months with a dedicated hot tub filter cleaner. Replace it immediately if you notice torn or collapsed pleats, permanent brown staining, or a pressure rise that doesn't clear after cleaning.