6" × 10-1/2"
Solana spa filters
Solana was a Hot Spring family line sold in the 2000s. Unicel does not list Solana by name; the fitment below comes from a dealer listing that assigns the Solana RX, SX, TX and Tx X models to the same 6" × 10-1/2" cartridge used in many Highlife spas.
Some Hot Spring-family tubs use a Tri-X ceramic filter of the same footprint instead of a pleated spa filter, so look at your current cartridge before ordering.
This page lists 1 Solana replacement cartridge from the Unicel 2026 Replacement Guide, the Pleatco 2023 catalog, the Filbur catalog and manufacturer and retailer pages, plus model and model-year fitment for 1 of them (4 hot tub models in total). 1 has a Filbur number. Find your spa filter by the OEM part number on the end cap, or measure it and compare sizes below.
Clean and replace intervals for one cartridge on this list, plus the cross-reference numbers and a buy link: filter replacement schedule and reorder.
| Cartridge | Unicel | Pleatco | Filbur | Size | Fits | Status |
|---|---|---|---|---|---|---|
| 31489; 71825; 71826 | C-6430 | PWK30-4 | FC-3915 | 6" (152 mm) × 10-1/2" (267 mm), 30 sq ft | 4 models | verified |
Know your model but not the part number? Solana models are listed in their own section of the Hot Spring filter by model and year lookup, from the same dealer table as the Hot Spring rows.
Brands that share cartridges with Solana
- Caldera, same part number C-6430
- Hot Spot, same part number C-6430
- Hot Spring, same part number C-6430
Guides that apply to Solana
- Tri-X care is a Highlife manual instruction
- Hot Spring family filter sizes
- Open-end vs threaded hot tub filters
- How Filbur, Unicel and Pleatco numbers compare
- How to find your spa filter size
- How to install a cartridge
- All guides
Search Solana part numbers on Amazon
Each button opens an Amazon search for that part number. The cartridge page is where the cited size and fittings are. Match those before you buy.
Part numbers from this table
-
C-6430 cartridge (OEM 31489)
Disclosure: we may earn a commission from qualifying purchases made through retailer links on this site, at no extra cost to you. As an Amazon Associate I earn from qualifying purchases. Amazon links on this page go to Amazon.com and are affiliate links; they never change what we write, and the list is not ranked by commission. Each “Search on Amazon” button opens an Amazon search for the part or product name shown, not a single listing we pre-checked. Check size, quantity and your spa maker’s guidance before you buy. See our affiliate disclosure.
Model-year fitment comes only from the sources named on each cartridge page. Where no source lists models or years, the page says so.