Scale in the Hot Tub

Scale in the Hot Tub

Published on Jan 03, 2020

Hot tub scaling is an issue that most spa owners will face at some point during the life of their spa. The scale itself is normally harmless and is a build up of minerals that deposit on the shell, fixtures or both. The scale can be unsightly and rough on the skin and if it's left unchecked, over time it can cause damage to the jets, plumbing, spa components and the shell. Knowing what do to remove existing scale and how to prevent it, is important and will keep your spa in tip top shape.


There are several different causes for scale build up: hard water, high alkalinity, high mineral content and body oils, lotions and other contaminants. Knowing which source is likely causing your issue is the first step to preventing scaling in the future. No mater which type of scaling you are suffering from, you will want to remove it as soon as possible and then take the appropriate steps to prevent it from occurring again.


Removing the scale buildup isn’t hard, as long as you are willing to put in some time and effort. You will need to scrub the affected areas to breakup the scale. Once you have removed the scale from the fixtures and inside of the tub, the particles should go through your filtration system and be collected. Once in the filtration system, remove and thoroughly clean the filter to completely remove the deposits from the spa.


Preventing the scale before it starts is really the key and will make keeping your hot tub clean a little easier. When keeping your spa clean, the filter is always a good place to start and preventing scaling is not different.

  • Remove and give your filter a thorough clean to remove dirt and contaminants from the filtration system. 
  • Clean any existing scale from the sides, jets and fixtures.
  • Check your pH and total alkalinity within the water. If you are suffering from high pH this can cause calcium to accumulate in the water causing scale to form. Same goes if you total alkalinity is high, however the pH and alkalinity tend to go hand in hand and if one is high then both are, and if one is low the other one probably is too. Keeping you water chemistry in the appropriate ranges is not only important in preventing scale build up, it will also prevent a host of other water chemistry problems. Ensure you are testing your water regularly and correcting the balance when necessary.
  • The source of the water, whether it be well water or city water can be the cause of the scale. If you live in an area where the water is harder, meaning it has more calcium in the water naturally, you are starting the spa with water that is more likely to cause scale. Try using a pre-filter to help remove minerals before they enter the spa, or you can also add a stain and scale prevention product right to the water to help fight scaling in your spa.
  • Having a regular cleaning routine including: draining, cleaning pipes of buildup, doing a chemical soak on the filters or replacing the filter as needed will help to cut down on scale producing contaminants in your hot tub.

Though scaling can be challenging to keep on top of, particularly when you are a new spa owner, making water maintenance and scheduled cleaning part of your regular routine can really help with preventing scale before it starts. That way you can spend less time worrying about unsightly scale and more time enjoy a relaxing, stress reducing soak in your spa.