"My hot tub just turned green." Here is how to fix it.

Nope…that green tint in your hot-tub isn't in your head—it has been invaded by algae. This issue can be tough to eradicate, but the good news is that you can get your water back to its pristine condition. And you can even stop it from returning with a few precautions. Keep reading to find out how you can get rid of green water.

Why is the water green?

The answer is…algae. When algae spores grow in your hot tub, the water often changes color. On top of that, an algae infection may also cause water cloudiness.

But how did this green monster creeps into your hot tub? There are a few factors that contribute to algae infection. Some of them include:

Leaving your hot-tub uncovered

Like plants, algae needs sunlight to grow. So when you leave your pool uncovered, you also leave the door open for algae.

Plus, without a proper cover, bacteria from debris and insects easily infect the water. Your hot tub thus becomes a marvelous home for algae to grow.

Low sanitizer

Algae feed on bacteria. Therefore, if you don't have enough sanitizer, you could end up with a nasty algae bloom.

Excessive metals

If your sanitizer levels are balanced, and you still have green water, then you might have excessive metals in your water. Where do metals come from? Things like your heat exchanger and source water can bring metals into your water. And when the metals react with the water, they may leave a green tint. 

Imbalanced water chemistry

Water chemistry is critical: when your water's chemical levels are out of whack, it becomes a breeding ground for algae. 

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What to do?

Once you've noticed that green tint, you can take a few steps to get your clear water back. Here's what you need to do:

1. Deep clean the hot tub

The first step is to drain and clean your spa. Once your spa is drained, clean every inch of the internal surface and ensure that it is free of bacteria and contaminants.

You can use a hot tub cleaner to get the job done, or opt for household bleach. Want a more natural cleaner? Distilled vinegar gets the job done, too.

2. Clean or replace your filter

Rinsing off your filter will not be enough if you face algae infection. Instead, you must clean it with a filter cleaner. You may also have to replace your filter altogether—depending on how old and worn it is.

3. Refill your hot-tub

Now that you've deep cleaned your hot-tub, it's time to refill it with fresh water. To ensure metals aren't entering your hot tub, use a hose filter, which removes minerals and other contaminants from the source water.

4. Clean your cover

Bacteria and algae spores can grow in unsuspecting places, like your spa cover. Therefore, make sure to perfectly clean your hot tub cover with diluted bleach or vinegar.

5. Shock your water

Once your pool is clean and refilled, it's time to shock it. Using a shock treatment will keep algae at bay. 

6. Test your water

After the shock is dissipated, test the water with a test strip (or even better, a smart monitor). Adjust the chemicals if necessary.

7. Balance, balance, balance

If your water test indicates an imbalance, add the chemicals accordingly. Then test the water again. If the water chemistry isn't where it needs to be, repeat the process until the chemical levels are ideal.

What should your chemical levels be? Here's a quick cheat sheet:

  • pH: 7.0 to 7.6;
  • Alkalinity: between 80 to 120 ppm;
  • Bromine: 3 to 5 ppm;
  • Chlorine: 1.5 to 3 ppm.

We know, managing chemical levels can get tricky. It takes time and energy.

The EcO Start digital pool monitor sends alerts to your phone when your spa's chemistry gets out of whack. It also sends you recommendations based on your hot tub's water quality.

How to prevent green water 🤷

Once you've said goodbye to algae, make sure it doesn't come back, with these prevention methods:

  • Cover your spa when it's not in use—even if it's not outdoors.
  • Ensure you're adding enough sanitizer based on your hot tub's volume. 
  • Regularly check your filtration system to ensure it's working and filtering out debris and contaminants.
  • Wash bathing suits or accessories you've used in any other pool or body of water before you allow them in your spa. Doing this will prevent bacteria and algae spores from contaminating your water.

Banish green spa water with iopool

Getting your spa water pristine and clean is a challenge. Indeed, it may take two or three trials before the algae infection goes away for good. However, iopool provides everything you need to win the war. 

Visit our shop to gather all the supplies you need.

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