A one minute tutorial to watch and learn quickly
Noticing white flakes floating in your hot tub water? We’ve been there. It’s a common issue many hot tub owners encounter, and it can quickly turn a relaxing soak into a maintenance headache.
The good news is, mold and flakes aren’t permanent. With the right approach, you can remove them and keep them from coming back.
Have you ever wondered what those white flakes are in your hot tub water? These flakes are often a form of algae called bacillariophyta. While they’re typically found in lakes and ponds, they can show up in hot tubs too, especially when water chemistry is off.
The good news? They're not harmful to humans. But if left untreated, they can cloud your water and leave a slimy film on spa surfaces.
We’ve found that the best way to prevent flakes is by staying on top of regular cleaning and balanced water chemistry. When your sanitizer levels are steady and your pH is in range, these invaders don’t stand a chance.
Keeping your water clear means less time troubleshooting and more time relaxing.
There are two main reasons for white flakes in your hot tub, and knowing which one you are dealing with will help you treat it properly. The two possible causes are calcium scale deposits and biofilm growth from white water mold.
If your water has high calcium or mineral content, it can leave behind scale deposits. When these minerals react with heat and air, they form a hard residue that breaks off into white or brown flakes.
These flakes often settle on surfaces or float in the water.
The other common cause is biofilm, often linked to white water mold, a type of bacterial contamination. This biofilm can appear as cloudy water or floating white flakes, and it tends to stick to surfaces such as the shell or jets.
Proper sanitation and regular cleaning are the key to preventing both issues.
Read more: How To Fix Hot Tub Biofilm Or Other Foul Contamination
If there are white flakes in your hot tub, don’t panic; a simple test can help you figure out what’s causing them.
What happens next tells you what you’re dealing with:
Quick, simple, and effective, this test helps you get your spa back to clean and clear.
White flakes often appear when biofilm or residue breaks loose from your hot tub’s plumbing. Over time, bacterial colonies form sticky biofilms inside the pipes and components. As these biofilms mature, fragments can detach, carrying bacteria and debris into the water.
Research confirms that biofilm detachment in water systems can impair water clarity and contribute to hygiene issues.
Here’s how we tackle it:
After draining, reinstall the filters and refill your spa with clean water. If you still see flakes, either repeat the process or wait for your filters to catch any remaining residue.
Tip: Be patient, this cleanup can take time, especially if the buildup was heavy.
Ready to make hot tub maintenance easier? Once your spa is clean again,use our store locator to buy O-Care.
White flakes in your hot tub are often a sign of biofilm, a slimy layer of bacteria that forms on surfaces and inside the plumbing. If left unchecked, it can cause cloudy water, foul odors, and even trigger algae growth.
To remove and prevent biofilm buildup, it’s essential to clean your system deep and maintain proper water chemistry. Start by flushing the lines and scrubbing every surface, including the hot tub cover, hot tub filters, jets, skimmer, and all other elements of the hot tub.
Don’t skip the plumbing. Biofilm loves to hide there. Once clean, shock the water and balance the hot tub chemicals to stop the bacteria from returning.
We’ve found that consistent care and chemical balance are key to keeping flakes, slime, and smells out for good.
For more help with water color issues, read our guide on green hot tub water.
Struggling to keep your hot tub clean? We’ve been there. That’s exactly why we created O-Care, a simple, natural solution that prevents buildup and makes water care feel effortless.
O-Care helps you stay ahead of problems like cloudy water, scale, and biofilm. With just a once-a-week dose, your spa water stays clean, soft, and safe. No more chemical guessing games or time-consuming routines.
"Benefits of this product can simply not be understated. While the price may initially raise an eyebrow, the reduction in overall cost of maintaining my hot tub has gone down. On top of that my skin is soft and my hot tub has become easier to maintain." - Bo Pablo on Trustpilot
Find a nearby O-Care store to elevate your hot tub experience with a product that is gentle on your skin, protects your equipment, and benefits the environment.
When dealing with calcium scale deposits in your water, it's important to ensure the pH and alkalinity are properly balanced. A calcium scale will form when the pH is too high, so you'll need to lower the pH and soften the hot tub water.
You can also use a scale preventer regularly, which will help break down existing particles and prevent the problem from occurring again.
Read more: Fix Calcium Scaling For Surprisingly Better Hot Tub Water
Here is a step-by-step guide to eliminate flakes in your hot tub:
There are a few simple things you can do to keep the flakes away for good:
Calcium flakes in your hot tub are usually caused by high pH or mineral content in the water. To fix the issue, flush the system, lower the pH, and use a scale preventer to remove existing buildup and stop it from returning.
Here are the details:
High pH is one of the biggest culprits behind calcium scale. If your water is too alkaline, calcium can harden and flake off. Test your levels and adjust as needed.
Keeping your pH in the ideal range is your first defense against buildup.
Many hot tub owners in hard water areas rely on a scale preventer. These products help neutralize minerals before they turn into flakes. Depending on the brand, you’ll add them monthly or quarterly.
Check with your supplier to find the right option for your spa.
Fluctuating temperatures encourage calcium deposits. We always recommend maintaining a steady water temperature to keep conditions stable and reduce mineral fallout.
Your filter traps more than just debris; it also captures calcium particles. Rinse it thoroughly every week and replace it as needed.
A clean filter keeps flakes from circulating back into the water.
Bonus Tip: Using a weekly solution like O-Care can make this whole process easier. It helps reduce chemical use, soften water, and limit scale buildup, all while being gentle on your skin and equipment.
Need more help with water chemistry? Read our guide on how to lower pH in a hot tub.
White flakes in your hot tub are often a sign of biofilm, colonies of bacteria that thrive in warm, moist environments like spa plumbing and filters. Studies show that when left untreated, these biofilms can contribute to skin irritation, unpleasant odors, and poor water quality over time.
The key to prevention is consistency. Stick to a cleaning schedule that includes:
White flakes in your hot tub are frustrating, but fixable. In most cases, you can remove them by flushing the system and running the pumps on high to clear out buildup.
To prevent flakes from returning, we recommend using O-Care. It’s an all-natural, enzyme-based treatment that breaks down organic matter and helps prevent biofilm, without disrupting your pH.
If you’re already dealing with biofilm, drain the spa, clean all surfaces thoroughly, and sanitize the system. Then switch to O-Care for easier, long-term maintenance.
Order O-Care today and enjoy clean, soft water without the hassle.
Here are some links to follow if you want to enhance your hot tub experience: