If you own both a swimming pool and hot tub, you used to have TWO different chemical products to treat each one. That's just how the EPA (Environmental Protection Agency) does things. Labeling matters. Pool chemicals for pools. Spa chemicals for spas & hot tubs. How about swim spas? Nobody knew! You had to have 2 different sets of chemicals for the pool and spa.
Pristine Blue is an easy to use, NON-chlorine, non-bromine chemical care system that can be used in all three. It is the only system that the EPA has approved since 1990) for use in all three! And even though it is a non-chlorine product, it is chlorine compatible unlike Baquacil or Soft Swim or Revacil or any other biguanide product.