Maintenance is important for any big investment, and a hot tub is no exception. Special chemicals are needed to keep your hot tub sanitary and to make sure that the water chemistry is properly balanced. Without them, bacteria growth and mineral buildup could damage your hot tub’s water heater and pipes, as well as promoting possible illness in hot tub users. However, it can be difficult to decide which hot tub chemicals to use in your spa. Here’s a short guide to some of the most common options and how they work.
Chlorine: You’re probably familiar with this chemical as a pool sanitizer. It’s used in a different concentration in your hot tub, so be sure to buy the right kind. You can purchase granules and tablets formulated specifically for use in hot tubs. Chlorine can also be used to shock a tub where the sanitizers have failed, or the upkeep of which has been poor. To do this, use a larger concentration of chlorine, and stay away from the hot tub for a day or so.
Bromine: This hot tub chemical comes in the form of granules, tablets, or nuggets. It also comes in a few forms. One is sodium bromide. This needs to be activated with an oxidizer. Chlorine is one. Potassium Monopersulfate, also called non-chlorine shock, is another. If you’d prefer not to have to activate your bromine, you can purchase BCDMH, a self-activating combination of chlorine and bromine. Many people prefer bromine for their hot tubs over chlorine since it’s less likely to off gas harmfully. Bromine can also work in a wide range of pH levels, so it’s less likely to stop functioning entirely if your water chemistry is off. Generally, bromine is distributed via a cartridge system or a floating feeder.
Biguanide: These sanitizers contain neither chlorine or bromine. Instead, they kill bacteria by attacking their cell walls. A hydrogen peroxide based oxidizer is used to burn off any organic matter, keeping the water clear. The benefit of biguanide sanitizers is that they produce less smell than either bromine or chlorine, and don’t off gas at the temperatures used in a hot tub.
Ozone: This is technically an oxidizer, not a sanitizer. However, it reduces the amount of work that you need to perform with sanitizers, lowering the level of hot tub chemicals you’ll need. To use ozone in your hot tub, you’ll need to have a type of equipment called an ozonator. Even with this device, you’ll still need to use a little chlorine or bromine, just not as much. Some say that ozone alone will sanitize a hot tub, but this is a myth. Ozone is compatible with almost all sanitizers.
Mineral Spa Care: Mineral systems can replace your sanitizers, but they can assist them. Generally, you’ll place a mineral cartridge inside your filter cartridge, or in a floating dispenser. Sanitizing minerals will then slowly disperse through the water, lowering the amount of chemicals you’ll need to keep your hot tub clean.