Hot Tub Treatment Guide
Download The Hot Tub Treatment Guide
Download a digital version of our hot tub water treatment guide so that you can easily refer to it whenever you need.
Download The GuideHot Tub Chemicals Guide
For a complete guide to ClearWater hot tub chemicals and water management, including dosage recommendations, click below for our hot tub chemicals guide.
Hot Tub Chemicals GuideShop Hot Tub Chemicals
Get all the chemicals you need for your hot tub. From chlorine granules and multifunction chlorine tablets, to pH regulators, find everything you need to treat and maintain your water.
Hot Tub ChemicalsStep 1 - Initially
After the hot tub is filled with fresh water
As soon as the hot tub is filled with water, you need a (booster) shock dose of Stabilised Chlorine Granules. This is a larger dose than normal to eliminate bacteria or contamination. Normally you need to aim for a Free Chlorine level of 3 ppm, but the booster dose will raise the Free Chlorine level to approx. 10 ppm and this high level needs to be maintained in the hot tub for a minimum of 2 ½ hours. This high level is likely to remain in the spa for at least 24 hours and will gradually drop over time. Only once the Free Chlorine levels fall between 3–5 ppm (after approx. 12 hours) can the hot tub be used.
How much stabilised chlorine granules do I need to add to my hot tub?
This depends on how many litres of water your hot tub holds
| LITRES | INITIAL DOSE RATE |
|---|---|
| 600 | 12g |
| 800 | 16g |
| 1000 | 20g |
| 1200 | 24g |
A teaspoon = approx 5g
Stabilised Chlorine Granules
The correct free chlorine level keeps the warm spa water
safe and bacteria free.
Step 2 - Daily
TESTING
Test your hot tub water using Clearwater® Dip Tests. The test strips will quickly let you know if the Free Chlorine, pH and Total Alkalinity levels are correct or need adjusting. Dip the strip into the water and remove immediately. Hold the strip level for 15 seconds (without shaking off excess water). Compare the strips results against the chart on the Dip Test container.
WARNING
Very high Chlorine levels can bleach the indicator on the dip test
ADDING CHLORINE
To maintain clean water that is safe to use, a daily dose of Stabilised Chlorine Granules may be required. Chlorine will be consumed even when the hot tub is not being used. If a lot of bathers are using the hot tub, you may need to increase the daily dose rates.
Ideal Free Chlorine level: 3–5ppm
| LITRES | INCREASE CHLORINE LEVEL BY 1PPM |
|---|---|
| 600 | 1.2g |
| 800 | 1.6g |
| 1000 | 2g |
| 1200 | 2.4g |
Step 3 - When Required
ADJUSTING THE pH LEVEL
The pH level of your hot tub water is important. Correct pH levels ensure that the hot tub water is comfortable for bathers and the water is neither too acidic or alkali. Unbalanced pH can cause skin irritation, scale formation, unpleasant smells, cloudy water, damage to components and fluctuating Chlorine levels.
Ideal pH range: 7.2–7.6
Clearwater® pH Plus is used to increase or
Clearwater® pH Minus is used to decrease
| LITRES | INCREASE OR DECREASE pH BY 0.1 |
|---|---|
| 600 | 6g |
| 800 | 8g |
| 1000 | 10g |
| 1200 | 12g |
ADJUSTING TOTAL ALKALINITY
Total Alkalinity (TA) is the measure of the water’s ability to neutralise acids. Balanced Total Alkalinity helps control the pH levels. Unbalanced TA can cause irregular pH and Chlorine levels and cause discomfort for bathers.
Ideal Total Alkalinity level: 80–120ppm
Clearwater® TA Plus is used to increase and
Clearwater® pH Minus is used to decrease
After the hot tub is filled with fresh water
As soon as the hot tub is filled with water, you need a (booster) shock dose of Stabilised Chlorine Granules. This is a larger dose than normal to eliminate bacteria or contamination. Normally you need to aim for a Free Chlorine level of 3 ppm, but the booster dose will raise the Free Chlorine level to approx. 10 ppm and this high level needs to be maintained in the hot tub for a minimum of 2 ½ hours. This high level is likely to remain in the spa for at least 24 hours and will gradually drop over time. Only once the Free Chlorine levels fall between 3–5 ppm (after approx. 12 hours) can the hot tub be used.
How much stabilised chlorine granules do I need to add to my hot tub?
This depends on how many litres of water your hot tub holds
| LITRES | INITIAL DOSE RATE |
|---|---|
| 600 | 12g |
| 800 | 16g |
| 1000 | 20g |
| 1200 | 24g |
A teaspoon = approx 5g
Stabilised Chlorine Granules
The correct free chlorine level keeps the warm spa water
safe and bacteria free.
TESTING
Test your hot tub water using Clearwater® Dip Tests. The test strips will quickly let you know if the Free Chlorine, pH and Total Alkalinity levels are correct or need adjusting. Dip the strip into the water and remove immediately. Hold the strip level for 15 seconds (without shaking off excess water). Compare the strips results against the chart on the Dip Test container.
WARNING
Very high Chlorine levels can bleach the indicator on the dip test
ADDING CHLORINE
To maintain clean water that is safe to use, a daily dose of Stabilised Chlorine Granules may be required. Chlorine will be consumed even when the hot tub is not being used. If a lot of bathers are using the hot tub, you may need to increase the daily dose rates.
Ideal Free Chlorine level: 3–5ppm
| LITRES | INCREASE CHLORINE LEVEL BY 1PPM |
|---|---|
| 600 | 1.2g |
| 800 | 1.6g |
| 1000 | 2g |
| 1200 | 2.4g |
ADJUSTING THE pH LEVEL
The pH level of your hot tub water is important. Correct pH levels ensure that the hot tub water is comfortable for bathers and the water is neither too acidic or alkali. Unbalanced pH can cause skin irritation, scale formation, unpleasant smells, cloudy water, damage to components and fluctuating Chlorine levels.
Ideal pH range: 7.2–7.6
Clearwater® pH Plus is used to increase or
Clearwater® pH Minus is used to decrease
| LITRES | INCREASE OR DECREASE pH BY 0.1 |
|---|---|
| 600 | 6g |
| 800 | 8g |
| 1000 | 10g |
| 1200 | 12g |
ADJUSTING TOTAL ALKALINITY
Total Alkalinity (TA) is the measure of the water’s ability to neutralise acids. Balanced Total Alkalinity helps control the pH levels. Unbalanced TA can cause irregular pH and Chlorine levels and cause discomfort for bathers.
Ideal Total Alkalinity level: 80–120ppm
Clearwater® TA Plus is used to increase and
Clearwater® pH Minus is used to decrease
Other Useful Information
How Often Do I Need To Drain & Refill My Spa?
To avoid a build-up of pollution from bathers, it is recommended to refresh the spa water by draining and re-filling every 2-3 months.
Why Is Water Circulation And Filtration So Important?
It is a combination of circulating the water and the cartridge filter collecting debris along with regular chemical treatment that keeps the spa water safe and crystal clear. Most spas include a pump to circulate the spa water and a cartridge filter to keep the water clear and free of debris. You should run your spa’s circulation every day referring to your spa Owner’s Manual for more detailed advice. Note, when the cartridge filter is dirty, filter efficiency and circulation is impaired often leading to cloudy water. Rinse the cartridge filter weekly with clean water to remove debris. For a more thorough clean, use ClearWater cartridge cleaner.