What Hot Tub Chemicals Do You Need?

The intention of this guide is to present a short tutorial on the basic hot tub chemicals. Water balance is the key to easy hot tub water care and this is affected by a number of factors including heat, sunlight, number of bathers, frequency of use, volume of water, condition of filters, body creams and hard or soft water areas. Even if some products are not part of regular water care, there are hot tub chemicals that you should always have at home.


1. Sanitiser

A hot tub sanitiser is a disinfectant chemical used to kill bacteria that develops within hot tub water, keeping it safe for bathers.

There are three types of sanitiser available chlorine, bromine and oxygen. Which one you choose to use will depend on your needs.

- Chlorine – The most popular hot tub sanitiser, chlorine is fast acting and effective at killing bacteria. Our chlorine hot tub maintenance guide explains more about how chlorine works.

- Bromine – Ideal for those with sensitive skin, bromine reacts slower than chlorine and is effective at killing bacteria. Find out more about maintaining you hot tub using bromine in our guide.

- Oxygen – A milder mineral solution, oxygen hot tub sanitiser is great for sensitive skin. Learn how you can use oxygen sanitiser in your hot tub in our oxygen maintenance guide.


2. PH increaser

Any pH level below 7.4 could spell trouble. The lower the pH level, the more acidic your hot tub water is. Highly acidic water makes it more difficult for your sanitizer to work effectively, leaving bathers in your hot tub exposed to potentially harmful contaminants.

This increases your chances of being exposed to bacteria, such as pseudomonas aeruginosa (the cause of hot tub folliculitis) or legionella (which causes Legionnaires’ Disease), among others. Low pH in your hot tub may also cause corrosion in spa components, which can be expensive to replace.

To increase the pH levels in your hot tub, add a pH increaser to bring the levels back to normal. It’s important to monitor the total alkalinity levels as the pH increaser will raise the TA level. Keep retesting the water to ensure the water is balanced.


3. PH decreaser

The pH decreaser is used when your pH levels climb beyond 7.6, your spa water can be described as basic. What this means for you is poorly sanitized water, carrying the same risks as any other cause of ineffective sanitizing.

Basic spa water is also prone to forming scale and drinking pumpkin spice lattes year-round. It really will cause flaky scale to build up on your spa surfaces.

The scale is due in part to high calcium hardness caused by the high pH. Cloudy water is another symptom of a high pH level in your spa.


4. Test strips

Out of all the hot tub maintenance tasks you’ll perform over the life of your hot tub, spa water testing is the one thing you’ll do more often than anything else. At least, it should be.

The only way you’re going to know whether the water contains any contaminants or what the chemical levels are is to test the water. And that means hot tub test strips are your best buddies.


5. Defoamer

In the hot tub, there are bubbles and there is foam. Big difference.  Bubbles are made as water is mixed with air and sent through the jets with force by a jet pump.  Bubbles help you relax and give a spirit of playfulness to your hot tub experience. Foam is the result of jet bubbles holding their shape after the jets are turned off. Foam forms because the water has contaminates such as body lotion, suntan oil or soap residue that hasn’t been oxidized or picked up by the filters. Bubbles form, are coated with “junk” and don’t pop!  Never get in a foamy tub. It’s a clear indicator that the sanitation is not at proper levels. No foam – helps cling to water pollutants such as perfumes and lotions, sinking them to the bottom of the tub to be taken through the hot tub filter.


6. Shock treatments

Spa Shock is a water treatment that oxidizes (gasses off) dead chloramines, body oils, sweat and other contaminates from your hot tub water.

Spa Shock is commonly available in two different forms. There is chlorine based shock (Sodium Dichlor), which increases your sanitizer levels as well as shocking the water, and non-chlorine shock (potassium monopersulfate or MPS) which is purely for oxidizing the water.


 If you have any other questions about pool and spa products please do let us know - we are here to help! 

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