Caldera Hot Tub Replacement Filters
Caldera shares a parent company (Watkins Wellness) with Hot Spring, but the cartridge sizing across Caldera's Utopia, Paradise, and Vacanza lines is its own thing. Some Caldera tubs use a single cartridge; some pair a fine cartridge with a coarser pre-filter cartridge. Check both filter compartments before you order.
The 11 Caldera models below cover the production from 2002 to present, which is where most cartridge-replacement questions land.
11 models indexed below
Caldera
→Kauai
5-person · 2003-present
Caldera
→Makena
6-person · 2003-present
Caldera
→Palermo
6-person · 2003-present
Caldera
→Montclair
7-person · 2003-present
Caldera
→Niagara
8-person · 2005-present
Caldera
→Geneva
7-person · 2005-present
Caldera
→Utopia
8-person · 2005-present
Caldera
→Vacanza
5-person · 2010-present
Caldera
→Salina
6-person · 2010-present
Caldera
→Marino
6-person · 2010-present
Caldera
→Oasis
6-person · 2002-2009
Quick tip: the fastest way to confirm the right cartridge is to pull yours and read the part number off the end cap. The owner's manual is the backup if the printing has worn off.