Routine Hot Tub Water Care & Maintenance


  1. Check the TA, pH and free chlorine/bromine are in the right range before each use and top up AFTER your bathing session.
    • You will learn how much chlorine or bromine you need to add on a daily basis as you get used to managing your tub.
    • You will find that the amount of sanitiser needed will change with the number of people, personal hygiene and length of time spent in the tub.
    • Add Pennosan Natural Spa Clarifier weekly, or more often if needed.
  2. Use a non-chlorine shock treatment once a week (or after a heavy bather load) or when the 6 way test strip tells you to.
    • Removes chloramines (in a chlorine sanitised tub) and frees up the chlorine to do its job.
    • Reactivates the bromine (in a bromine sanitised tub) so that it can do its job.
  3. Use a 6 way test strip once a week so that you can keep an eye on the Combined Chlorine and CYA (cyanuric acid, stabiliser) levels.
    • Combined chlorine is calculated by subtracting Free Chlorine from Total Chlorine. Combined chlorine should be kept as low as possible (ideally, zero), less than half the free chlorine and always less than 1ppm.
    • Whenever you add stabilised chlorine to the water, you are adding CYA. Unlike chlorine which gets used up, CYA builds up in the water. Always aim to keep CYA to a minimum. As CYA rises, so the efficiency of the chlorine drops. When CYA reaches 100-150ppm or above, it’s time to change the water. You should aim to keep CYA to a minimum, which is why we do not recommend to shock with stabilised chlorine.
  4. Change the filters regularly.
    • Weekly if you have a hard-shell tub, up to daily if you have an inflatable.
    • Have at least two filters in rotation (3 or 4 if you have an inflatable and use daily).
    • Clean filter and allow to dry before reusing.
    • Always keep spares.