Why does my spa water get cloudy?

We often receive questions from our customers about cloudy water in their spa. We've put together a quick guide that will help you identify what is causing the cloudy water and provide some tips to help fix it.


Always follow the directions on your chemical container label

This guide is for general reference only. Always follow the directions on your chemical container label.

1. Change your filters regularly

Make sure you are changing your filters regularly and in line with your spa manufacturer's recommendations. We recommend changing your filters every 3-4 months.


2. Rinse your filters every week

Your spa filters are often neglected though they are the best way to keep your water crystal clear.

Spa filters need to be washed off weekly. We suggest a filter wand as the most effective way of doing this without damaging the filter material.


3. Soak your filters in a filter cleaning solution

On a monthly basis, you need to soak your filter in an approved filter cleaner solution to eliminate body fats and other organic matter that are not removed by simple rinsing.

Most people rotate 2 sets of Spa filters so that they can soak one set while the other is in use. Adhere to the guidelines of your filter cartridge cleaner label.

Do not use products like nappy cleaners as most of them contain bleach which reduces the life of your spa filters.

4. Balance your pH and Alkalinity 

Your spa water pH should be within the range of 7.2 to 7.8. Total Alkalinity should be within 80-120 PPM.

Use water test strips to check your pH and Total Alkalinity.


If your water is not in these recommended ranges, modify up or down using an approved pH decreaser or Alkalinity increaser until it is appropriate. Make sure to follow the instructions on your chemical labels and give the substances a chance to work before examining again.

For more advice on pH and Alkalinity read our detailed guide: "What is spa water Alkalinity and pH?"

5. Shock your water once a week

 You need to use an approved oxidiser (spa shock) at least once a week or after heavy use (say a party in the weekend with lots of guests in your spa!). Spa shock oxidises the organic matter that makes the water cloudy.

Important: If you are using a chlorine-free sanitising system you will need to shock the water with a Chlorine-free shock (Poppits Quick Fix). 


Read our article on Spa Shock for more detailed information.


6. Use the right amount of sanitiser 

Make sure you are dosing your spa water with enough Sanitiser. Underdosing your Sanitiser can cause cloudiness. Ensure you follow the recommended dosage on the sanitiser label.

7. Use a water clarifier (especially with bore water or rain water)

If you are using bore or rainfall water and have followed the recommendations above but your water is still cloudy you may use a water clarifier or flock. Study the guidelines on the label for dosage rates. Essentially the water clarifier works by grabbing microscopic particles of organic matter and combining them into larger particles where they can quickly be captured in the filter media.



8. Use an algicide to remove phosphates and algae

If you are using Poppits sanitiser or another brand of Hydrogen Peroxide you might have an algae issue. Please read this post for details on troubleshooting algae in spas.

Use an Algicide product to help clear algae.


Cloudy spa water and Purezone spa filters


Follow the dosing instructions so that you do not prematurely plug your filter. Spa chemicals take time to work. Be patient.

Important: Purezone filters can be gently rinsed as needed. They cannot be soaked in a filter cleaning solution. Purezone filters must be replaced at least every three months depending on bather load.

If you have any queries contact our helpful staff.

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