Too Much Chlorine in Pool (Best tips to lower it)

Swimming pools are a popular form of recreation and exercise, but maintaining the right levels of chemicals is essential for both health and safety. One of the most common chemicals used for pool sanitation is chlorine due to its proven effectiveness in killing bacteria and other germs. However, the presence of too much chlorine in a pool can lead to various harmful effects on swimmers and the pool itself.

Understanding the risks associated with too much chlorine in a swimming pool is crucial for both pool owners and swimmers. Regularly testing and maintaining proper chlorine levels can help prevent these problems while ensuring the safety and enjoyment of everyone using the pool.

chlorine feeder

Table of Contents

Too Much Chlorine in Pool

Excess chlorine in a pool can lead to a decrease in pH levels, which can cause the water to become more acidic. This can result in skin irritation, eye irritation, and over-dilated blood vessels in the eyes. Furthermore, if the pH level is too low, chlorine may lose its effectiveness in sanitizing the pool, leading to unsafe swimming conditions. Therefore, it is important to maintain a proper balance of combined chlorine levels and pH levels in the pool. The ideal maintenance pH level for a pool is between 7.2 to 7.8, and the recommended chlorine level is 2-5 ppm.

Understanding Pool Chlorine

Pool chlorine is a widely used disinfectant that helps to keep swimming pools clean and safe from bacteria and algae growth. It is important to maintain an appropriate chlorine concentration to protect swimmers from potential health issues and to prevent damage to pool surfaces and equipment.

Chlorine in pools exists in two forms: free chlorine and combined chlorine. Free chlorine is the active form of chlorine that disinfects the water by killing harmful organisms. 

Combined chlorine, on the other hand, is formed when free chlorine reacts with contaminants in the water, such as sweat, urine, and other organic matter. This creates chloramines, which are less effective as disinfectants and can cause unpleasant odors and other issues.

Pool chlorine levels are typically measured in parts per million (ppm). The recommended concentration of free chlorine for most pools is between 1 and 3 ppm. This is generally sufficient to keep the water clean and safe for swimming while avoiding the side effects associated with excessive chlorine levels.

Maintaining the correct chlorine concentration is essential to prevent potential health problems for swimmers, such as skin irritations, eye irritation, and breathing issues. High chlorine levels can also have a negative impact on pool equipment and surfaces by causing corrosion.

Total alkalinity is another important parameter to consider in pool water chemistry. It serves as a buffer, stabilizing pH levels and preventing fluctuations that can impact the effectiveness of chlorine and other sanitizers. 

An adequate total alkalinity level ensures that the chlorine in the pool works efficiently and avoids the degradation of surfaces and equipment.

chlorine poisoning

The Impact of Excessive Chlorine in Pool

High chlorine levels can cause skin, eye, and lung irritation. Prolonged exposure to excess chlorine may result in dry skin and hair, skin irritations, or itchy skin. 

Additionally, swimmers may develop rashes or hives and experience eye irritation, coughing, and pain in the nose or throat. For individuals with asthma, high chlorine levels can cause wheezing and even lead to asthma attacks.

Not only can excessive chlorine be harmful to swimmers’ health, but it can also damage the swimming pool structure and equipment. 

Over-chlorinated pools often have higher acidity levels in the water, increasing the likelihood of corrosion. This can affect the pool’s metal piping, surfaces, liners, concrete, and tiles, eventually leading to costly repairs and replacements.

A safe level of chlorine in a pool is between 1-5 parts per million (ppm). Should the level rise above 10 ppm and the pH level fall below 7.0, it is recommended to drain and refill the pool to avoid potential harm to swimmers and the pool itself.

skin hives

Detecting High Chlorine Levels

There are several methods for testing chlorine levels in pool water. One of the most common approaches is to use a testing kit or testing strips. These tools measure the concentration of both free and combined chlorine, which are essential for effective sanitation and disinfection.

For a more accurate assessment, a DPD test kit can be employed. This method involves adding reagents to pool water samples, which react with chlorine to produce a color change. 

The intensity of the color is then compared to a reference chart, enabling a precise measurement of chlorine concentrations.

It is important to be aware of chloramines, which are byproducts formed when chlorine reacts with organic substances. Chloramines can cause discomfort and irritation to swimmers while also reducing the effectiveness of the chlorine’s disinfectant properties. 

Therefore you need to monitor the levels of both free and total chlorine to ensure accurate detection of any issues.

Aside from using a testing kit, there are some visible and olfactory signs that can indicate high chlorine levels. When the pool water becomes cloudy or exhibits a strong odor, this could be an indication of excessive chlorine concentrations. 

In such cases, further testing should be carried out to confirm the cause and implement appropriate remedial actions.

High Chlorine Levels

Symptoms of Over-Chlorination

One of the most common symptoms of over-chlorination is irritated eyes. Swimmers often experience red, watery eyes when the chlorine levels in a pool are too high. This irritation occurs because chlorine can strip away the protective film that coats the eye, leading to dryness and discomfort.

Skin irritation is another common symptom of over-chlorination. High levels of chlorine can cause dry, itchy skin, and in some cases, a rash may develop. Over time, this can also lead to an increase in skin sensitivity, making it more prone to further irritation.

In addition to skin irritation, swimmers may also experience dry hair and nails as a result of over-chlorination. Chlorine can strip the natural oils from hair and nails, leaving them brittle and prone to damage. 

This can be particularly frustrating for those who swim regularly, as their exposure to high chlorine levels is ongoing.

While most of the symptoms mentioned above are relatively mild, over-chlorination can also lead to more severe reactions in some individuals. Burns can occur when extremely high levels of chlorine come into contact with the skin, causing painful, red, swollen areas that require immediate attention.

Another serious symptom of over-chlorination is difficulty breathing. This can occur when the chlorine in the pool reacts with sweat and organic material, creating chloramine gas. 

If this gas is inhaled, it can cause respiratory problems, including coughing, chest tightness, and shortness of breath.

red eyes from chlorine

Getting Rid of Excessive Chlorine

One method to lower high chlorine levels is by using a chlorine neutralizer like sodium thiosulfate. Sodium thiosulfate, also known as a chlorine reducer, works by breaking down the chlorine molecules into harmless substances. 

To use it, simply follow the instructions on the product label, making sure to add the correct dosage for your pool’s size and current chlorine level.

Another option is to utilize ascorbic acid, which is a type of vitamin C. This antioxidant can also neutralize chlorine by forming a harmless compound. To apply ascorbic acid in your pool, make sure to follow the specific guidelines on the product to avoid under or overdosing.

Hydrogen peroxide can also function as a chlorine neutralizer. When added to the pool water, it reacts with chlorine to form water and oxygen, thereby reducing the chlorine concentration. 

Keep in mind that hydrogen peroxide can affect the pool’s pH levels; as a result, it is essential to monitor and adjust the pH as needed.

Dilution is another simple method to lower chlorine levels. By adding fresh water to the pool, you can reduce the concentration of chlorine. However, this method may not always be practical, as it can lead to an increase in water consumption and might cause the water level in the pool to become too high.

Sodium sulfite and sodium metabisulfite are alternative chemical options to reduce excessive chlorine. Both of these chemicals work similarly to sodium thiosulfate by breaking down the chlorine molecules. 

When using either of these options, make sure to follow the guidelines provided by each product to ensure effective and safe application.

Lastly, it is important to remember that proper pool maintenance is crucial to prevent excessive chlorine levels. Always follow manufacturer’s instructions when adding chlorine tablets to your pool and regularly monitor chlorine levels to avoid any issues. Don’t forget that maintaining a balanced pH, adequate filtration, and circulation are also essential for healthy pool water.

diluting pool

Maintaining Correct Chlorine Levels

Maintaining correct chlorine levels in swimming pools is essential to ensure a safe and enjoyable swimming experience. To achieve this, it is crucial to monitor the pool’s chlorine and pH levels regularly using test strips. 

The test strips will provide a quick and accurate reading of the chlorine and pH levels in the water.

One approach to reducing excess chlorine in the pool is to expose it to sunlight. Sunlight naturally breaks down chlorine, making it an eco-friendly solution for maintaining proper pool chlorine levels.

In addition, pool owners should address any fluctuations in pH levels as needed, as maintaining the appropriate pH range (between 7.2 and 7.6) will ensure that chlorine effectively destroys bacteria and other contaminants in the water.

Consistently monitoring and maintaining proper chlorine and pH levels will help in providing a safe and enjoyable swimming environment while minimizing potential damage to pool equipment and surfaces.

pool ph

Role of CYA in Chlorine Regulation

Cyanuric acid (CYA), commonly known as a stabilizer, plays a crucial role in regulating chlorine levels in a swimming pool. It is essential to striking a balance within pool water chemistry to maintain a healthy and clean environment for swimmers.

CYA works to protect chlorine from the sun’s ultraviolet (UV) rays. When chlorine levels in the pool are left exposed to UV rays, the sanitizer in the water can degrade rapidly, leaving the water prone to the growth of unwanted bacteria and algae. With the addition of CYA, chlorine molecules in pool water are shielded from these harmful UV rays, allowing the sanitizer to maintain its effectiveness for a longer period. This results in stable chlorine levels and reduces chemical expenditure.

However, it is important to keep the cyanuric acid levels within an optimal range, typically between 30-50 parts per million (ppm). If CYA levels exceed the ideal range, it can lead to a decrease in the chlorine’s efficiency. Higher CYA levels, particularly above 100 ppm, can cause chlorine molecules to bind, making it difficult to kill algae and bacteria that may be present in the water. In such cases, pool professionals may recommend a water change to bring the CYA levels back to the ideal range and restore the chlorine’s efficacy.


regulation cya

Effects on Hair and Skin

Swimming in a pool with too much chlorine can have various negative effects on the hair and skin. Chlorine is a chemical added to pools to kill harmful bacteria and keep the water clean. 

However, when present in excessive amounts, it may cause issues such as skin irritation, dry hair, and even hives.

One of the most common effects of too much chlorine is dry, brittle hair. Chlorine strips away the natural oils that protect and moisturize the hair, leaving it more prone to breakage and damage. 

Over time, frequent exposure to high concentrations of chlorine may cause discoloration and split ends.

Skin irritation is another concern when swimming in a chlorinated pool. Many individuals experience redness, itchiness, and scaling due to the harsh nature of chlorine on sensitive skin. 

In more severe cases, excessive chlorine can lead to the development of hives or contact dermatitis, an itchy rash caused by exposure to pool chemicals.

People with pre-existing skin conditions, such as eczema or psoriasis, may find that their symptoms worsen after spending time in a pool with too much chlorine. 

It’s important to note that the severity of these side effects often depends on factors like age, the amount of time spent in the water, and the overall balance of chemicals in the pool.

brittle hair

Chlorine Vs. Other Disinfectants

There are several alternative disinfectants that pool owners can consider for maintaining their swimming pools.

One notable alternative to liquid chlorine, is bromine. Similar to chlorine, bromine is a powerful disinfectant and algaecide. It effectively eliminates bacteria and microorganisms in the pool water, while being less affected by the heat and sunlight compared to chlorine. 

This property makes bromine a more stable option, especially for hot tubs and spas. However, it’s worth noting that bromine tends to be more expensive than chlorine and needs more frequent monitoring throughout the day.

UV rays also serve as an excellent method for pool water treatment. Ultraviolet sanitizing systems work by emitting UV light to destroy microorganisms without adding chemicals to the water. 

This ensures minimal irritation for swimmers and a more eco-friendly option. However, UV systems need to be combined with a minimal level of chemical disinfectants for optimal sanitation, as the UV light only targets the water that passes through the circulation system, not the water in the pool itself.

uv rays

Chloramine: A Byproduct of Chlorine

Chloramine is a chemical compound formed when chlorine reacts with organic substances found in pool water, such as sweat and urine. The presence of chloramine, also known as combined chlorine, is often the cause of the strong chlorine smell in swimming pools. 

Contrary to popular belief, this distinct odor indicates that there might not be enough free chlorine in the pool to effectively neutralize the contaminants.

To eliminate chloramines, pool operators need to raise the chlorine level significantly through a process called “shocking” or “super-chlorination.” This involves adding a large dose of chlorine to the pool, which breaks down the molecular bond of chloramines, allowing them to evaporate.

While it may seem ironic to add more chlorine to a pool that smells strongly of chlorine, this process actually helps restore the proper chemical balance in the water. 

Pool owners should regularly measure the combined chlorine and free chlorine levels to keep chloramines in check and ensure a safe swimming experience for everyone.

chlorine on poolside

Safety Measures and Precautions

It is crucial to maintain safe chlorine levels in a swimming pool to prevent potential health risks and ensure a comfortable swimming environment. Taking appropriate safety measures and precautions can help to manage chlorine levels effectively and avoid any unwanted consequences.

To lower pool chlorine levels that are too high, try the following methods:

  • Dilute the pool water by partially draining it and refilling it with fresh water.

  • Allow the sunlight to naturally break down the excess chlorine, as the UV rays help to reduce chlorine levels over time.

  • Use a chlorine neutralizer, available in many pool supply stores, that can help bring down chlorine levels quickly and effectively.

Another way to prevent excessive chlorine levels in a pool is to implement proper chemical storage and handling procedures. This includes securing the storage area to limit access and ensuring that appropriate safety gear, such as goggles and gloves, is used when handling chlorine.

safety measures

People Also ask

How to reduce high chlorine levels in a pool?

There are several ways to reduce high chlorine levels in a pool:

  1. Stop adding chlorine: Refrain from adding any more chlorine to your pool until the levels are balanced.

  2. Use sunlight: Allow the sun’s UV rays to naturally break down the excess chlorine.

  3. Dilute with water: Partially drain your pool and refill it with fresh water to dilute the chlorine concentration.

  4. Turn on the heater: Increasing the water temperature can help speed up the process of chlorine dissipation.

  5. Test your pool often: Regularly check your pool’s chlorine levels to ensure they remain within the ideal range.

What are the side effects of swimming in a pool with too much chlorine?

Swimming in a pool with excessive chlorine levels can cause several side effects:

  • Eye irritation

  • Coughing

  • Pain in the nose or throat

  • Triggering asthma symptoms

  • Lung irritation

  • Damage to swimsuits and pool surfaces

What chemicals can be used to lower chlorine levels?

Aside from letting chlorine naturally dissipate, you can use chemicals specifically designed to neutralize excess chlorine in the pool water. Sodium thiosulfate, commonly referred to as chlorine neutralizer, is one such product.

What is the ideal chlorine level in a pool?

The ideal chlorine level in a swimming pool should be between 2.0-4.0 parts per million (ppm) to maintain cleanliness and prevent bacteria growth without causing harm to swimmers.

Can high chlorine levels affect pH balance in swimming pools?

Yes, high chlorine levels can affect the pH balance in swimming pools. When chlorine levels are too high, the acidity of the water may also increase, leading to a lower pH level. This can cause problems such as metal corrosion and damage to pool surfaces, liners, and tiles.

How long should one wait to swim after reducing chlorine levels?

It is recommended to wait until the chlorine levels have returned to the ideal range of 2.0-4.0 ppm before swimming. This can take anywhere from a few hours to a couple of days, depending on the methods used to reduce chlorine levels and the initial concentration. Regularly test your pool water to ensure it is safe for swimming.

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Oliver Wright
Oliver Wright

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