Hey there! The Spa Guy here with a simple but critical part for your Watkins spa. This gray standpipe cap does double duty – it locks your filter cartridge in position and marks exactly where your FreshWater Ag+ Silver Ionizer should go if your tub has multiple filter wells.
I've installed hundreds of these caps on Hot Spring, Tiger River, Hot Spot, and Solana models over the years. The gray color isn't just for looks – it's your visual guide to the correct standpipe when you're swapping out your silver ion cartridge. No more guessing which filter location is the right one!
This cap works with an enormous range of models from the early '90s right up to 2025 units – Grandee, Envoy, Aria, Jetsetter, Sovereign, you name it. Cross-references to part numbers 36513, 78932, and 78782. At $14.99, it's a small investment that keeps your filtration system working exactly as Watkins designed it. Need help figuring out if this fits your setup? Just reach out!
