Spa Frog Serene® (Bromine) Cartridge - Purple 7.1 oz - 33% More Bromine

The Spa Frog Serene® (Bromine) Cartridge is for use in the Serene In-Line System for hot tubs and spas.

This purple bromine cartridge contains 33% more bromine than the standard yellow bromine cartridge. 

Size: 7.1 oz 

The Serene (Bromine) cartridge is the active sanitizer in this system. Use in combination with the Spa Frog blue Mineral cartridge, found here.

Not sure how to maintain or start up your hot tub on this system?
Download the Spa Frog Serene (bromine) In-Line System operating instructions here.

Please Note: Spa Frog makes Serene® bromine cartridges in yellow, green and purple. The purple and green are high capacity 7.1 oz / 200 gram cartridges which contain 33% more bromine than the yellow 5.3 oz cartridges.

If your hot tub has the Spa Frog In-Line System installed, and you are on Spa Frog Serene® (bromine), you can use either the yellow, green or purple Spa Frog Serene® (bromine) cartridges.

If you are using the Spa Frog Serene® (bromine) Floating System, only the yellow Spa Frog Serene® (bromine) cartridge can be used. You can find the Spa Frog Serene® Combined Cartridge Kit here, which can be used in both the Serene® Floating System and the In-Line System.