How to Prevent and Remove White Flakes in a Hot Tub

How to Prevent and Remove White Flakes in a Hot Tub

How to Prevent and Remove White Flakes in a Hot Tub

Have you ever noticed white flakes floating in the water or gathering by the drain of your hot tub?

You’re not alone! This collection of white flakes isn’t uncommon for hot tub owners. However, the pesky flakes will just continue to accumulate until you do something about it.

The good news? There are some simple things you can do to remove them and prevent them from forming again in the future.

Cause of white flakes

What is the reason behind your white hot tub flakes? There are two primary causes of the formation of white flakes in a hot tub – calcium scale deposits and biofilm.

Calcium Scale Deposits

Calcium scale deposits occur when there is an excess of calcium in your hot tub water. This high-calcium water is commonly known as “hard water.” As calcium accumulates in your water over time, white flakes will start to form. Because calcium levels depend on the pH of your water – and because correct pH levels can be tricky to maintain – this is most likely your problem.

However, this may not always be the case. 


If a nasty film (a biofilm)  is collecting in your water, you may very well have a bacteria problem. Biofilm is made up of naturally occurring materials – like algae, white water mold, fungus, or any airborne contaminants – that generally collect in warm, moist environments. 

Biofilm primarily collects when your hot tub has been unused for a long period of time without being properly cleaned. The warm and moist nature of a hot tub makes it a prime spot for mold and other bacteria to form – which produces the white flakes.

However, biofilm can also collect with active, regular use of your hot tub. Body oils, dead skin cells, lotions, cosmetics, and other organic material naturally shed by those using the hot tub only speed up biofilm formation.

How to determine which type of flakes you have

Before you can get rid of the white flakes, you have to determine the cause. 

Fortunately, doing so is simple! Use a cup or a bowl to take approximately a 4 to 8-ounce water sample (with some flakes floating it in). Add 15 to 20 drops of bleach or liquid chlorine to the water, and allow the sample to sit for 30 minutes. 

If the flakes disappear by the end of the 30-minute waiting period, you are most likely dealing with a biofilm buildup. However, if the flakes remain, it is probably a result of excess calcium scale deposits.

Removing and preventing white flakes

The necessary process for white flake removal and prevention depends on the kind of flakes you have in your hot tub.

If you have calcium scale deposits…

Make sure that your pH alkalinity is properly balanced in order to remove the white flakes. Calcium scale deposits begin to form when the pH levels of your water are too high. Therefore, you will need to bring them down with the proper acidic chemicals.

First, use a test strip and the Rising Sun Pools water testing app to check your pH and alkalinity levels. 

Remember, your total alkalinity – a big influence on pH levels – should fall somewhere between 80 and 120 ppm and your pH level should remain between 7.2 and 7.8. Navigate to the Rising Sun Pools water testing web app to receive recommended dosages and treatments for your pool.

But, how can you prevent calcium build-up in the future?

Use a calcium scale preventer on a regular weekly basis. It will help you break down existing calcium particles in your water, preventing the problem from occurring again. Need an expert-recommended scale preventer? Stop by one of the Rising Sun Pools storefronts, today.

If you have any questions about your spa and calcium scaling, please don’t hesitate to contact us. Rising Sun Pools also offers hot tub maintenance packages to help keep your spa in top shape year-round!

If you have biofilm… 

You will need to do a full, thorough clean and water treatment of your spa to get it back to remove the white flakes. Make sure you clean the hot tub cover, filters, skimmer, and all other elements of your tub. Then, you will need to shock the water to kill all remaining bacteria.

Once you are finished shocking the tub, drain it completely, wipe everything down, and clean it thoroughly. Once the entire tub has been successfully cleaned, you can fill it back up with water.

Rising Sun Pools offers all the precise chemicals you will need for a proper hot tub cleaning and shock.

READ MORE: Quick Tips For Cleaning Your Hot Tub

To prevent biofilm buildup from happening again, just check and balance your water consistently and clean your hot tub on a regular basis. The Rising Sun Pools team recommends a full drain and deep clean every 3 to 4 months and a good filter cleaning every 3 to 6 weeks.

Rising Sun Pools – Hot Tub & Spa Installation & Service in Raleigh, NC 

Not only do Rising Sun Pools hot tubs and spas offer the very best in both quality and design, but our team ALSO offers a full line of hot tub and spa maintenance, programs, and products.

Need some hot tub maintenance help? Learn more about our spa maintenance services here.