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How to Get Rid of Algae, Mold, and Mildew in Your Hot Tub

Do own a hot tub? Spa maintenance is relatively easy and successful when you follow a simple schedule for regular ongoing maintenance.

If you keep your hot tub clean and maintained, algae, mold, and mildew don’t usually grow. But, what happens if you end up with these issues or a musty, moldy odor when soaking?

If something is growing in your hot tub, it’s important to figure out what caused it, how to get rid of it, and how to prevent it from returning.

Let’s look at how to get rid of algae, mold, and mildew in your hot tub.

What Causes Hot Tub Algae, Mold, and Mildew?

Algae, mold, and mildew are very different organic substances. Mold and mildew are fungi, and algae are plants.

Algae in a hot tub can take many forms and can appear in various colors, from green to yellow to white to black. Your water could appear greenish or cloudy. Or the sides of your hot tub shell could feel slippery and slimy to the touch.

Algae generally forms in a hot tub when the pH levels in the water are imbalanced. They can also occur when not enough sanitization chemicals, such as bromine or chlorine, have been added. Sunlight makes algae flourish, so leaving your hot tub uncovered for extended periods of time also encourages algae growth.

Mold and mildew can take the form of floating white slime in your spa water or discolored white or black patches on your hot tub shell.

  • Mildew is a surface fungi that can usually be easily wiped away
  • Mold might be a sign of a more intensive infestation.
  • Mold is most likely to form in a neglected spa. You can get mold from by soaps, lotions, or other substances that have been transferred to the hot tub from the skin of a bather.
  • It often establishes itself in the filters, jets, or plumbing and begins to grow.
  • Mold and mildew also frequently first appear on a hot tub cover, then spread to the water.

How to Fight These Problems

Algae, mold, and mildew will not grow in a clean and properly sanitized tub.

If they do occur, you can treat minor problems by adjusting your pH levels. This brings your spa water back to the proper balance. Then you can shock your tub water with sanitizer.

To ensure your problem is gone for good, you may need to drain your tub after shocking it.

After you drain your spa, clean the shell with a gentle cleanser. Make sure to clean the jet nozzles as well. You also want to clean or replace your filters before refilling your spa. The above video shows you how.

What about extreme contamination? Shock the water with sanitizer once more after refilling it, then drain, clean, and refill it again. This can be a time-consuming process, but it’s worth the effort. You will eliminate all traces of the contaminant and restore your spa water back to pristine condition.

For Moldy Covers

If your hot tub cover is moldy, give it a thorough cleaning. Remove it from your hot tub to clean it. Follow up with a conditioner like Hot Spring Cover Shield™ to keep your cover in good working condition for longer.

You want to clean your hot tub cover regularly even if you don’t see mold.  It’s worth noting that if your cover has grown increasingly heavier over time with water saturation, it might be time to replace it. A waterlogged hot tub cover is abreeding ground for mold.

How to Prevent Algae, Mold, and Mildew

Keep your tub covered when it’s not in use. Make sure your filters are cleaned and replaced according to a regular schedule. Follow the instructions of your water care system for testing and maintenance.

If you do these things and stay on top of your hot tub sanitation, you won’t likely experience significant problems with water contaminants.

Need help with algae, mold, or mildew? Our service department stands ready to help!

Fill out this form and we’ll get in touch with you as soon as we can.

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