Ultraviolet Light UV
As the name suggests, an ultraviolet (UV) sanitation system uses UV-C germicidal light rays to help keep your hot tub water clean and free of bacteria. The UV remains in a sterilization chamber within the hot tub’s piping, so it does not actually enter the hot tub. This system helps prevent organic matter like algae and bacteria from reproducing by disrupting the DNA or RNA of these organisms. UV sterilization is an effective sanitizer; however, it does not oxidize the water so you will still need to oxidize the water with chlorine, bromine or a non-chlorine shock product.