What To Do If Your Pool Has Too Much Chlorine

Nick Durante
by Nick Durante
Credit: Shutterstock / Allison H. Smith

The luxury of a swimming pool is something that many homeowners want. However, it comes with a lot of work and maintenance that can be hard to keep up with. It’s all too easy to go overboard and over treat a swimming pool. That’s why you may struggle with what to do if your pool has too much chlorine.

Drain 1/3 to ½ of the water in your pool if it has too much chlorine, and replace it with fresh water. Chlorine neutralizers that contain sodium thiosulfate can also quickly reduce the chlorine level in a pool. You can also find pool-grade hydrogen peroxide at pool supply stores that help maintain alkalinity and chlorine levels.

If you want to avoid using chemicals, you can uncover your pool and let the sunlight do the work for you. Follow along as we explore what to do if your pool has too much chlorine.

How To Tell If A Pool Has Too Much Chlorine

The only way to tell if your pool has too much chlorine is to test the water. Never swim in a pool that has more than 3.0-5.0 parts per million of chlorine. That is too much chlorine, and it can irritate your skin and eyes.

Swimming pools become especially dangerous if the chlorine level reaches 7-10 parts per million. Excessive chlorine can impact the pH level in your pool and throw it off the balance. The water can eventually become acidic, and that can damage the walls and tiles in your pool.

Don’t assume that your pool has too much chlorine if it smells strongly like chlorine. That smell simply indicates that the chlorine is doing its job. You will smell the chlorine more strongly when it’s actively disinfecting your pool and killing bacteria.

How Do I Quickly Lower The Chlorine Level In My Pool?

1. Replace The Water

While you don’t need to replace all the water, you can fix your chlorine problem if you replace some of the water in your pool. At most, you may need to replace ½ of the water in your pool if the chlorine level is high. However, you can typically fix the problem if you simply replace a third of the water.

Simply drain water from the pool then refill it. Keep in mind that this can take all day depending on how big your pool is. Make sure to check the chlorine level after you refill your pool.

Be patient as you may need to drain more water again if the chlorine level is too high. Don’t swim until the chlorine level is between 1.0 and 3.0 parts per million. Check the pH level, since quickly adding a lot of water can throw off the pH level in your pool.

2. Rely On The Sun

Sunlight is the most natural way to reduce the chlorine level in your pool. Granted, this can take a while, but it’s a great option if you don’t want to run up a huge water bill or use chemicals. Sunlight is full of UV rays that significantly reduce the chlorine content in your pool.

This process only works if you uncover your pool and stop putting chlorine in the water. Avoid using cyanuric acid as it makes it take longer for chlorine levels to drop. Let your pool sit in the sun for 2-4 hours, then check the chlorine level.

It doesn’t take long for the level to drop because sunlight eventually turns the free chlorine into gas. Continuously test the water until the chlorine is at 2-3 PPM. Be patient, as the process can take a while if your yard has lots of trees and doesn’t get much sunlight.

3. Neutralize The Chlorine

Sometimes, you must rush to find a solution when you accidentally put too much chlorine in your pool. Luckily, it’s easy to make your pool safe to swim in if you neutralize the chlorine with one of many available products. Chlorine neutralizers typically contain sodium thiosulfate, which reduces the total chlorine content in a swimming pool.

It’s important to carefully read the directions when you use a chlorine neutralizer. You only typically need to add one cup of neutralizer per 5,000 gallons of water in your pool. That said, it varies based on which chlorine neutralizer you use.

Be careful not to add too much neutralizer to your pool as this can remove all the chlorine. That’s the last thing you want, as algae is more likely to grow in your pool without chlorine. Harmful bacteria can also thrive, so you must only use the amount of neutralizer that your pool can handle.

4. Use Hydrogen Peroxide

Hydrogen peroxide works to lower both the chlorine and pH levels in a pool. That said, you can’t simply pour raw hydrogen peroxide into the water. Many pool supply stores sell hydrogen peroxide preparations that you can safely use in pools.

You can only use this method if your pH level is at 7.0 or above. Otherwise, the hydrogen peroxide will lower the pH level in your pool too much. Never use medical-grade hydrogen peroxide to lower the chlorine level in your pool.

Simply follow the directions on the pool-ready peroxide preparation you buy. It doesn’t take as much as you may think, and a little goes a long way.

5. Turn On The Heater

Do you have a pool heater? If so, you can use it to reduce the chlorine content in your swimming pool. Chlorine evaporates much faster when it’s hot, especially if the temperature is over 90 degrees.

Turn your pool heater to 90-100 degrees for at least 30 minutes to help lower the chlorine level. You don’t need to run the heat for too long, but it depends on how much chlorine is in the water. Running the heat that high for too long can be quite expensive.

How Long Should You Wait To Swim After Adding Chlorine?

Ideally, you should wait at least 4 hours to swim after adding chlorine. It can take up to 8 hours for the chlorine to reach a level that is safe for swimming. Check to make sure the chlorine level is at 1-3 PPM before you swim.

That said, you should wait 24 hours to swim after shocking your pool. Shocking a pool entails adding an extreme dose of chlorine to a swimming pool. This is a great way to quickly get rid of contaminants, algae, and bacteria.

It’s unsafe to swim in a freshly-shocked pool because it can irritate your skin, eyes, and lungs. Luckily, you can typically swim within 30 minutes after you balance the alkalinity or use a stabilizer. However, you must read the directions on the label of any chemical you use. Follow the recommended waiting period to avoid problems.

Summing It Up

Replace 1/3 to ½ of the pool water with fresh water if your pool has too much chlorine. You can also reduce the chlorine in your pool if you uncover it and let the sunlight turn the chlorine into gas. Run your pool heater if you have one to reduce the chlorine level as well. Otherwise, you can use hydrogen peroxide and chlorine neutralizers.

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Nick Durante
Nick Durante

Nick Durante is a professional writer with a primary focus on home improvement. When he is not writing about home improvement or taking on projects around the house, he likes to read and create art. He is always looking towards the newest trends in home improvement.

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