What to Do With Green Hot Tub Water?

If you find green water in your hot tub, this means that its chemical imbalance has caused it to malfunction. It can also prevent you from safely using the tub.

In this post, we will explain what causes hot tub water to go green and how to prevent it from happening again.


What Makes Hot Tub Water Turn Green

Lack of Sanitiser in the Water / Algae Growth

It is most likely that the water has not been sufficiently salted to prevent the algae from growing. This causes the algae to form and grow. This issue may be caused by the excessive usage of the hot tub. It is known to cause the chlorine to become less effective and reduce the efficiency of the sanitiser.


Excessive Metals

If your sanitiser levels are at or below 3ppm, then you may have a green tint in the water. If they are at or above this level, then the metals in the water may have excessive levels.


How to Clear Green Water from a Hot Tub

Shock the Water and Clean Filters

To remove algae from water, start by killing off the algae and ensuring that the water has a good clean. This will help remove the green algae and bring the water back to a normal sanitiser level.

For a 1,000L hot tub, this dose will provide you with a chlorine or bromine level of over 10ppm. To avoid staining your pool or spa, make sure to remove your cover immediately after this dose.

Once it has started to clear, it is time to clean the hot tub's filter. This will help remove any dead algae from the water.


Drain and Refill

If the water in your system is not recovering using the above method, then you have the option of draining and refilling with fresh water. This method works best if the system is not draining correctly.

If you are worried about the presence of metals in the water, such as copper, iron, and brass, then use a pre-filter that will remove these contaminants from the water.


Tips to Prevent Green Water in a Hot Tub

- Ensure your levels are always within range - Chlorine/Bromine 3-5ppm. PH 7.2-7.6. Alklainity 80-120ppm.

- Use a pre-filter when filling if concerned with metal content in the water.

- Keep you filter clean and degreased using a filter cleaner. Filtration assists with sanitisation.

- Drain your hot tub every 3-4 months and use a pipe flush to remove biofilm.


 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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