HotSpring Tri-X Filter Part Number: 73178 This Spa Filter is designed to fit the following hot tubs and spas: Caldera Tahitian 2005 to Current, Caldera Niagara 2005 to Current, Caldera Geneva 2005 to Current, Caldera Aspire 2004 to2008 and Caldera Elation 2003 to 2010. Can replace the 71825 filter in all 1990 to current Hot Spring spa models, 1998 to 2002 Hot Spot models and all Solana X, RX, SX and TX spa models. ref 73250 ref 0969601 No matter the model of your spa or hot tub, or when it was made, it's important that you regularly change your filter to prevent bacteria buildup. Choose from our selection of hot tub filters to find the right replacement hot tub filter for your spa, at the right price. Hot Spring Spa filters are a vital part of any spa system. Spa filters regulate the water that enters your spa and keep debris, dirt, and other items from floating into the pipes and damaging the pump and inner workings of your hot tub. Hot Spring Spa Supplies carries spa fragrances, air and water valves, control systems, filter accessories, lights, cleaners, pumps, thermostats, and more for virtually every hot spring model.