How to Fix Cloudy Hot Tub Water

Nothing puts a damper on relaxing in your hot tub like realizing the water looks less than clean. Cloudy water has a few different causes and is a common hot tub maintenance issue. Luckily, most of these problems have easy fixes, so let’s talk about getting your hot tub water back into the best shape.

The common causes of cloudy water are a filter not functioning properly, an imbalance of chemicals, or contamination from outside sources.

Water Filter

If your hot tub filter is dirty or not working properly, it cannot remove contaminants and small debris from the water. It can also cause the pump to work harder, which can cause damage to the pump parts if not fixed.

To remedy this, make sure to rinse your hot tub’s filter once or twice a month, and wash it with filter cleaner about every three months. You should also drain the water in your tub and completely replace it at the same time as the thorough filter cleanings. Once a year, get a new filter to install in your tub.


Chemical Imbalance

The amount of chemicals used to sanitize your hot tub, typically bromine or chlorine, can be too low, causing an imbalance and resulting in cloudy water. If the alkalinity or calcium hardness is too high, it can cause carbonate ions to un-dissolve, form precipitation, and create cloudy water.

If the level of sanitizer is too low, simply add more chlorine or bromine (whichever you have been using) to the water and allow it to circulate for a few minutes. You can then use test strips to ensure that the amount of sanitizer is at an effective and safe level.

If alkalinity is too high, you can adjust it by adding a chemical like sodium bisulfate. If the calcium hardness is too high, a water softener or additive can help to lower the levels. At times, it may be easier to drain some water from your tub and replace it from a source that has lower calcium hardness.

Be sure to check the alkalinity and calcium hardness once adjustments have been made by using test strips or another test kit. Remember that it takes some time for any additives or changes to take effect, so do not perform too many corrections at once and test as you go.



Every time you get into your hot tub, you bring any contaminants that may be on your skin or hair. Lotions, hair products, oils, dirt, and other particles will soak off into the water and may cause cloudiness. It is best to shower or rinse off before getting into the tub to prevent the problem, but there are ways to resolve dirty water if it happens.

One option is to add a chemical “shock” to the water that uses an oxidizing agent to break down the particles that are introduced when you use the tub. Other options are to use a chemical “clarifier” that binds to particles so that they can be trapped by the filter, or use enzymes to break down the contaminants.

The first step to correcting water cloudiness is to identify the cause. Once you know the cause, you can treat the problem appropriately so that it does not return and enjoy a beautiful, clear spa.


Need Help Maintaining Your Hot Tub?

For help with cloudy hot tub water, or other hot tub problems in Connecticut, contact your local trusted hot tub service provider – Aqua Pro Pool & Spa Service: