How to Remove and Prevent Hot Tub Scale

by Matt Giovanisci | Last Updated: December 13, 2016

There is nothing worse than looking in your hot tub only to find hot tub scale on the shell or your fixtures.

Hot tub scale is a problem every hot tub owner must face. Knowing what to do to remove the scale and then prevent it from happening again is key. While it may seem difficult, the truth is, if you know what to do, it’s quite easy. Today we take a closer look at hot tub scaling and what you need to do to remove it and prevent it from returning to your hot tub.

What Is Hot Tub Scale?

Hot tub scale is the buildup of minerals in your hot tub over time. These minerals can often be seen in the water and can even buildup on your shell or your fixtures. While it normally isn’t harmful, it doesn’t look very good and over time it can even damage your fixtures and clog your plumbing if you allow it to buildup unchecked.

Hot Tub Scale Sources

There are many different causes of hot tub scaling. Knowing what the source of your scaling issue is key to prevention. In most cases, hot tub scale is caused by:

  1. Hard Water
  2. Highly Alkaline Water
  3. Water with High Iron or Calcium
  4. Body Oils, lotions or other contaminants

No matter what kind of scaling you have, you should remove it immediately and then take the proper steps to prevent it from building up again.

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How to Remove Hot Tub Scale

Removing hot tub scaling isn’t complicated, but it will take a little bit of elbow grease to get the job done. You will need to scrub the affected areas with a hot tub scale remover to break up the buildup. Once you have broken the scaling away from your shell and fixtures, it should make its way to your filter. You can then clean the filter to completely remove the built up scaling from your hot tub.

In some cases, simply cleaning your hot tub while there is water in it won’t be enough. If you can’t get the scaling removed while your hot tub is filled with water, drain your hot tub. Then, using hot tub scale remover, break apart and remove any bits of scaling found on the sides and fixtures of your hot tub.

Preventing Hot Tub Scaling

Prevention is really the key when it comes to hot tub scaling. You may not be sure where to start when it comes to scaling prevention, but that’s why we are here. Below you find many different suggestions on what you should do to prevent hot tub scaling from ever becoming a problem in your hot tub.

Clean Your Filter

Before you do anything else, make sure you give your filter a good cleaning to remove any potential contaminants from your hot tub’s filtration system.

Remove the Existing Scaling

After you have cleaned your filter, scrub the sides and the fixtures of your hot tub to remove any existing scaling. For more information, see the section above on removing hot tub scaling.

Check Your pH

The recommended pH range for your hot tub’s water is between 7.4 – 7.6. High water temperatures in your hot tub can make the pH level climb. A high pH level can cause calcium to build up on the surface of your hot tub. Bring down the pH levels back to their optimal range and the build up of calcium will stop.


Total alkalinity is like a buffer for pH. Basically, it is the ability of your water to neutralize acids. If your alkalinity is high, chances are your pH will be high as well. On the other hand, if your alkalinity is low, your pH level will probably also be low. There are exceptions to this rule, of course.

Total alkalinity should be kept somewhere between 80 – 120 parts per million. Once you get your TA levels correct, you will have a much easier time maintaining your pH levels. This will help you control the amount of scale build up in your hot tub.

Water Softeners and Filters

The quality of your source water can sometimes be an issue. In some areas, the water is harder than others. This means that more calcium is present in the natural water. Every time you fill up your hot tub, you have already started down the scaling path.

To stop this, try using a filter that will remove some of the minerals in the water while you fill your hot tub. If that doesn’t do the trick, you can purchase and add water softeners to reduce the minerals present in the hot tub.

Use Scale Prevention Products

You can also try using a scale prevention product in your water to reduce the scale present in your water. These products are easily added to your hot tub after you add the water and will make your life so much easier if you have been fighting scale build up in your hot tub.

Clean Your Hot Tub

One of the best ways to put a stop to scaling it to regularly clean your hot tub. This means cleaning the sides and all the fixtures of your hot tub and regularly cleaning and sometimes even replacing your filter. This will ensure that all scaling particles are removed from your hot tub so they don’t clog your system or cover your fixtures and your shell.

Final Thoughts

Hot tub scaling can be frustrating, especially for new hot tub owners. Understanding your water’s chemical makeup and regularly treating and cleaning your hot tub is key in preventing scale build up. If you do get a little scale in your tub, it’s not the end of the world. Just be prepared for a little hard work to remove it.

At the end of the day, prevention is the key. By following the suggestions above, you should be able to prevent scale build up before it happens. That way you can enjoy a soak in your hot tub without that ugly sight of scale on your fixtures and shell.

Happy Soaking!

Matt Giovanisci, the founder of Swim University®, started in the pool and spa industry at age 13 and moved to bigger companies along the way, helping thousands of pool and hot tub owners every year. He wanted to share his knowledge and unique teaching style on a larger scale, so he launched Swim University® in 2007. Since then, he's worked to make pool and hot tub care easy for over 10 million homeowners. And each year, he continues to help more people with water chemistry, cleaning, and troubleshooting.

Learn How to Keep Your Hot Tub Clean and Clear All Year Long

You'll save $100 right away with this easy-to-follow digital ebook and video course. This is the guide that hot tub manufacturer doesn’t provide you.

Click here to learn more
The Hot Tub Handbook