How To Lower Chlorine Levels in Your Swimming Pool

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You will need to reduce chlorine levels someday if you own a pool or spa. Chlorine is vital in maintaining proper pool chemistry, but too much chlorine results in eye irritation and coughing. Luckily, you can correct high chlorine levels in your pool with a few hacks.

Keep reading the article to learn how to reduce pool or spa chlorine levels.

Why Is My Chlorine Level So High?

The chlorine level of your pool might be high because you’ve added too many chlorine granules or because you left your liquid chlorine pump running for more time than needed. If this last situation happened, your pool water will be green. 

If you use Cyanuric Acid, a chlorine stabilizer, it will protect the chlorine in the pool from ultraviolet rays, slowing down its natural degradation. If you add more chlorine stabilizers, reduce the amount of chlorine you use in the pool.

Excess chlorine stabilizer is not ideal either as it will render the chlorine ineffective. Thus, the chlorine will not bond well with contaminants. Use the tips below if the CYA levels are very high.

  1. Drain your pool to half.
  2. Add water to normal levels.
  3. Using a pump, circulate the water for a few hours. Make sure fresh water mixes with existing water.
  4. Test the pool stabilizer levels.

Consult with a professional if the stabilizer levels are still high.

Bear in mind that you need different amounts of chlorine at different times of the year. For instance, ultraviolet rays will reduce chlorine levels by 90% on a sunny day. The same applies to pools that see a large number of swimmers.

Well circulated pools require less chlorine, making them more fun to swim in.

How High Is Too High for Chlorine?

The ideal chlorine range is up to 5ppm. If chlorine levels exceed 5ppm, it can lead to skin and eye damage and lung irritation.

Excess chlorine makes the water more acidic, causing dermatitis often characterized by red bumps. As the pH level of the pool water changes, swimming becomes uncomfortable.

Frequent swimmers will have their fabric shred and elastics break down. Regular exposure to excess chlorine will also turn your swimwear yellow. If your swimsuit changes its appearance, close the pool until chlorine falls back to normal levels.

How To Test Very High Chlorine Levels

Most chlorine test kits detect a maximum of 10ppm. If the DPD test sample produces a flash of pink and then goes clear, it’s a good indication the pool water has excessively high chlorine. Add distilled water to the test sample, and double check the results you get.

How To Reduce Chlorine Levels in the Pool

Start by turning off your chlorine generator at the control unit. Use the tips below to lower the chlorine levels.

1. Leave the Pool Uncovered for a Few Days

Chlorine will disintegrate on its own if you leave the pool uncovered for a week. Over time, ultraviolet rays break down chlorine, reducing its effectiveness.

Avoid swimming in the pool until chlorine falls back to the recommended levels. Don’t add chlorine to your pool. Instead, let nature work its magic.

2. Use Chlorine Neutralizer

You can use sodium sulfite or sodium thiosulfate to lower chlorine levels. Add the sodium sulfite gradually to avoid removing excess chlorine.

Add half cup scoop but remember to check specific instructions from the manufacturer. Compare the pH levels before and after using the neutralizer.

3. Drain and Refill the Pool

You can drain the pool and add fresh water. By draining the pool, you dilute the existing water and reduce its alkalinity.

Chlorine in the pool is diluted, so ensure to test the water after draining the pool. Adding fresh water will alter calcium hardness levels in the pool.

4. Use the Spa or Pool

It’s not easy to reduce chlorine levels by 3ppm. Fortunately, you can achieve this by using the spa or pool.

Ask your family members and friends for a swim. In the end, they will contribute to reducing the chlorine to an acceptable level. However, don’t swim when the chlorine levels are above 10ppm, as this can cause skin infections.

5. Use Hydrogen Peroxide

You can use hydrogen peroxide to counteract chlorine in your pool. As a pool oxidizer, a 35% concentration of hydrogen peroxide will break down chlorine. The sanitizing chemical is also used in commercial swimming pools as an antiseptic to kill bacteria.

Hydrogen peroxide is a perfect way to make your swimming pool more natural. However, it should be used in the correct ratio of one cup to 250 gallons of water.

6. Add Vitamin C aka Ascorbic Acid

Vitamin C will work magic if your pool has high chlorine levels that must be reduced quickly. Ascorbic Acid or Vitamin C acts as a reduction agent when used in a pool.

It’s the recommended chlorine detoxifier because it’s not toxic to humans and sea life. You can use Vitamin C on fiberglass surfaces.

Reducing High Chlorine in Hot Tubs

You can use Vitamin C (Ascorbic Acid) or Hydrogen Peroxide to reduce chlorine levels in hot tubs. Leave the hot tub uncovered and run a jet pump for a few hours. The hot tub will lower chlorine levels on its own.

If the hot tub has high chlorine or bromine levels, replace chlorinated water with fresh water. While you can drain chlorinated water without help from a professional, you must wait for hours for the chlorine to fall to normal levels. Draining your hot tub or pool does not need any chemicals or neutralizers.

How Long Does It Take for High Chlorine Levels to Go Down?

Leaving your pool uncovered and exposed to direct sunlight might reduce chlorine levels in four hours. However, it depends on the concentration of chlorine granules.

If the chlorine exceeds 10ppm, it takes around 24 hours to lower chlorine levels. Use highly concentrated hydrogen peroxide to expedite the process.

How Do I Know That My Pool Has Too Much Chlorine?

Swimmers will emerge from the pool red eyed if your pool has excess chlorine. You might also experience a burning sensation in the eyes and signs of skin irritation. When your hair feels dry after swimming, it’s time to reduce chlorine in the pool.

Can You Swim in a Pool With High Chlorine?

Regular swimming in chlorinated water may lead to lung irritation, aggravating asthma symptoms. It’s dangerous to swim in too much chlorine as it causes eye damage and skin infection. Swallowing pool water with high chlorine could expose the swimmer to parasites like Giardia.

What Does Too Much Chlorine Feel Like?

Swimming in an over-chlorinated pool makes you more susceptible to lung irritation, especially if you have chronic obstructive pulmonary disease. If you swim for an extended period in chlorinated water, you will notice symptoms of dryness and irritation of your skin.

Before swimming in chlorinated water, understand how your skin responds to bromine or chlorine water. Chlorine poisoning is associated with coughing and difficulty breathing. Rinse your eyes and skin with distilled water if you notice blistered skin and blurred vision.

Does High Chlorine Make the Pool Cloudy?

Your pool becomes cloudy because of an imbalance in the chemicals. Alkalinity and high chlorine levels are the leading causes of cloudy pools.

Excess calcium hardness in your pool water will also make your pool cloudy and damage plumbing. Thus, you need to correct pool water chemistry and eliminate contaminants in the water.

How to Clear a Cloudy Pool

To get rid of cloudy water in your pool, check any broken parts. Clean the filter media thoroughly and remove any debris trapped in the skimmer basket.

Should I Shock the Pool if Chlorine Is High?

Use a non-chlorine shock if your pool or spa is over-chlorinated. You can shock your pool weekly to maintain the chlorine balance.

Can I Add Shock and Chlorine at the Same Time?

Although chlorine and shock effectively eliminate algae, they should not be used together. Shock the pool first, and then add chlorine.

How Long After Shock Can I Add Chlorine?

You need to wait for one hour before adding chlorine to the pool. Be sure to test the pH levels before letting anyone in the pool.

How Long Should I Run My Pool Pump After Shocking?

Use a pool filter or pump for at least six hours after shocking.

Conclusion on Reducing Chlorine Levels

No matter which method you choose to lower chlorine levels, test the pool water to ensure chlorine levels have decreased. If you swim in a pool with too much chlorine, moisturize after swimming, and don’t swim in the pool if it’s over-chlorinated. Swimming in too much chlorine water will cause chemical injuries and potential chlorine poisoning. 

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