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  • Writer's pictureWellis

How to shock your hot tub step-by-step

Why you need to shock your hot tub?


1. Shock removes organic contaminants such as shampoo, makeup, lotion, sunscreen and even dead skin cells and prevents it to build up over time causing scum or cloudy water your hot tub.


2. Shock kills bacteria. Hot tubs are incubators for harmful bacteria and shocking it regularly will help you to keep it free from them.


3. Shock removes chloramines and bromamides. When chlorine or bromine kills all bacteria and removes organic contaminants from the water produces waste products called chloramines or bromamides - pending on which one you use in your hot tub to sanitise it. This causing your water smell. Hot Tub shock eradicates chloramines / bromamides and brings your sanitiser levels up and steady.


Regularly shocking your hot tub will help you to keep your water crystal clear free from all scum and harmful bacteria.💦



What type of Shock should you use?


1. Some types of shock eradicate all contaminants while others only work for some of them. We recommend Dichlor Shock for your hot tub. Dichlor is the active ingredient in all brands of hot tub shock and it contains a small amount of cyanuric acid. It kills all types of contaminants. Keep an eye on your sanitiser level though when you shock and make sure you shock in the evening to keep the sun’s rays from eating away the chlorine too quickly.


2. Non-chlorine shock is not a disinfectant and it does not kill bacteria. It is an effective oxidiser though and when used weekly can do a great job getting rid of organic contaminants like lotion or dead skin cells and clearing your hot tub’s water if it becomes cloudy. It also actives “free” chlorine/bromine which is needed to kill bacteria.



Which spa shock should you use?


That depends on which sanitiser you use. If you use chlorine or bromine use chlorine shock but make sure your chlorine levels are between 1-3 PPM (parts per million). You can also use non-chorine to keep your water clear between regular chlorine shocks but if you do that test often and never let your chlorine level drop lower than 1 PPM. If you use your hot tub a lot we recommend sticking with chlorine shock regularly even if you use a bromine sanitiser.


If you use Biguanide sanitiser use biguanide shock.


If you use mineral sanitiser in your hot tub, use a non-chlorine shock. You will still ad a little chlorine to get the full sanitising effect but your chlorine level should only be around 0.5 PPM.


If you use salt water in your hot tub use chlorine shock or non-chlorine shock.


And if you use UV, Ioniser or Ozonator sanitising system in your hot tub, use chlorine shock. Dichlor is compatible with all these systems but you should always follow the manufacturer’s instructions.



What do you need to shock our hot tub?


1. You’ll need the right hot tub shock

2. Chemical resistant measuring cup

3. Test strips

4. Chemical resistant gloves

5. Safety Goggles



How to shock your hot tub step-by-step:


1. Open your hot tub and leave your cover off through the procedure. Once you add shock some of it needs to off gas from the water.


2. Test the water - Before shocking your spa the pH must be at the correct level between 7.4 – 7.6. If not at the right level, adjust it, then continue with the shocking.


3. Turn off the jets – the circulation pump needs to be on, but not the jets because the water becomes too agitated.


4. Put on the safety glass, googles and long trousers and closed shoes. If your hot tub is indoors turn on the ventilation and/or open the window. Either way make sure the room has good ventilation before you use any chemicals.


5. Measure the shock – make sure you use the correct amount of shock for the amount of water you in your hot tub. If you are not sure, have a look online on our website to know the exact litres of water you have in your spa.


6. Shock your hot tub – carefully add the shock to the water as described by the shock’s manufacturer.


7. Leave the hot tub uncovered for at least 20 minutes to allow the shock to fully dispel and dissipate. After 20 minutes you can put the cover back on to prevent evaporation.



When you can use your hot tub again?


You can use your hot tub after the sanitiser level dropped back to where it supposed to be. Test the water after shocking and check the manufacturer’s instructions.


You’ll need to shock your hot tub every week and always check the water before to make sure the pH and sanitiser levels are correct. Always read the manufacturer’s instruction before you add any shock to your hot tub.



Source: Swim University

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