Hot Tub Chemistry 101

Your new hot tub is installed and filled with warm soothing water. You’re ready to step in and relax. But have you thought about the chemistry? Proper hot tub maintenance is crucial for the longevity of your new investment. Keeping your tub clean and sanitized is as important for the operation of the hot tub as it is for the safety of the people in it.

Let’s take a look at the important chemicals used in maintaining your new spa.


The reality is that certain bacteria and viruses will be able to survive and thrive in the warm water. It is important to keep the water disinfected and clear.

There are two popular sanitizers:

Chlorine – An excellent sanitizer but comes with unpleasant chlorine odor.

  • Cost-effective
  • Easy to apply
  • Aggressive bacteria killer

Bromine – Popular choice for tubs and indoor pools, no chlorine odor*

  • Effective algae killer
  • Kills bacteria for longer than chlorine

*Not ideal for outdoor pools and spas: the sun’s UV rays break down Bromine faster

Shock Treatment (Oxidizer):

Spa shocks work much like sanitizers and are used to kill any bacteria, algae, or bad odors your daily sanitizer may miss. Shock treatments can be considered support for your sanitizer and are applied based on how often your hot tub is used.

Shock Treatments typically come in two forms.

Non-Chlorine – A monopersulfate compound (MPS), oxygen based and used in regular maintenance

Dichlor – A form of chlorine used as both a sanitizer and a shock, typically used only when you refill your hot tub.

Shock treatments oxidize (gasses off) old chlorine, oils, sweat, dirt, and other contaminants that can make your water cloudy and smelly.


Think of clarifiers as magnets for those tiny particles of dirt and dust that are too small to be caught by the water filter. They attract and gather up these particles making them large enough to become trapped in the filter, thus keeping your hot tub’s water looking clean and clear.

Many clarifiers are somewhat selective in what they will and won’t attract. Be sure to read and follow instructions to ensure using the right clarifier for your specific needs.


Two very important things you must test regularly in order to maintain a healthy spa system are alkalinity and pH levels. Different balancers will be used to increase and decrease the alkalinity and pH levels as they are needed.

Alkalinity is a pH stabilizer and should be measured before checking the pH levels. Maintaining proper alkalinity will prevent fluctuations in the pH level.

It is extremely important to monitor your spa’s pH levels.

Too low and you run the risk of equipment corrosion, skin and eye irritation, and lowering the overall efficiency of your spa system.

Too high will make your water cloudy, lower the efficiency of your sanitizer, and cause skin and eye irritation as well.


These chemicals are intended for general cleaning and maintenance. They help keep your spa’s filter cartridges, cover, and shell like new.

Never use household chemicals to clean your spa and its accessories or you run the risk of damaging its appearance or functionality. Specially made cleansers will allow you achieve the best results without harming your investment.

With so much to keep track of it can feel overwhelming for the first time spa owner but the experts at Creative Energy will be there to guide you through every step. If you’re thinking about a new spa or just need a little help maintaining yours, stop by one of our locations or contact us today!