Why Does My Pool Water Smell Like Chlorine?

A strong chlorine smell indicates chloramines. Shock the pool to break them down and restore clean water.

Why Does a Pool Smell Like Chlorine?

The smell of chlorine comes from chloramines, which are formed when chlorine binds to contaminants like sweat, body oils, urine, and sunscreen. Chloramines are different from free chlorine, which is the active sanitizer that keeps your pool water clean. When chloramines build up, they cause eye irritation, skin discomfort, and a noticeable chlorine-like smell.

Common Causes of Chloramine Buildup

1. Not Enough Free Chlorine: If there is not enough free chlorine in the water, it cannot effectively sanitize the pool.
   

2. High Swimmer Load: More people in the pool mean more sweat, body oils, and other contaminants that chlorine has to fight off.
   

3. Poor Pool Maintenance: If the pool is not regularly shocked, chloramine levels can increase.
   

4. Inadequate Filtration: A clogged or underperforming filter allows contaminants to stay in the water, contributing to chloramine formation.
   

5. Low pH Levels: When pH drops too low, chlorine becomes less effective, leading to an increase in chloramines.
   

How to Get Rid of Chlorine Odor in Your Pool

If your pool smells like chlorine, follow these steps to eliminate the odor and restore water balance:

1. Test Your Water

Start by checking your pool’s chemical levels using a test strip or liquid test kit. Focus on these key measurements:

• Free Chlorine: Should be between 1-3 ppm.
  

• Combined Chlorine (Chloramines): Should be below 0.5 ppm.
  

• pH: Should be between 7.4-7.6.
  

• Total Alkalinity: Should be between 80-120 ppm.
  

If free chlorine is low but combined chlorine is high, you need to shock the pool to remove chloramines.

2. Shock Your Pool

Shocking the pool adds a high dose of chlorine to break down chloramines and restore proper sanitation. Use one of the following shock treatments:

• Calcium Hypochlorite (Cal-Hypo): Best for regular chlorine-based pools.
  

• Sodium Dichlor: Works well for pools with high stabilizer levels.
  

• Non-Chlorine Shock (Potassium Monopersulfate): Effective for maintaining clear water without adding more chlorine.
  

Shocking should be done at night to prevent the sun from burning off the chlorine before it works.

3. Improve Circulation and Filtration

A weak or dirty filter allows contaminants to stay in the water, increasing chloramine formation. Take these steps to ensure your filtration system is working properly:

• Run your pump at least 8-12 hours per day to keep water circulating.
  

• Clean or backwash your filter regularly to maintain efficiency.
  

• Check for clogs or blockages in skimmer baskets and pump intakes.
  

4. Maintain Proper pH and Alkalinity

Unbalanced pH and alkalinity levels can make chlorine ineffective. Adjust your water chemistry as needed:

• If pH is too low, add sodium carbonate (soda ash).
  

• If pH is too high, add muriatic acid or sodium bisulfate.
  

• If alkalinity is too low, add baking soda to bring it back within the ideal range.
  
  

5. Reduce Contaminants Before Entering the Pool

Prevent chloramines from forming by keeping the pool water as clean as possible:

• Shower before swimming to remove body oils and sweat.
  

• Encourage bathroom breaks to prevent urine from mixing with chlorine.
  

• Use a pool cover to minimize debris and organic contaminants.
  
  

6. Consider Using Pool Enzymes

Pool enzymes help break down organic contaminants, reducing the burden on chlorine. Adding enzymes can help keep water clearer and reduce the chlorine smell.

Preventing Chlorine Odors in the Future

Once you have balanced your pool water, take these steps to prevent chlorine odors from returning:

• Shock the pool weekly to eliminate chloramines before they build up.
  

• Maintain proper chlorine levels by testing water regularly.
  

• Run your pump and filter consistently to keep water circulating.
  

• Check and clean pool filters to prevent contaminants from accumulating.
  

• Encourage good hygiene habits among swimmers.
  
  

Keeping Your Pool Fresh and Clean

A strong chlorine smell in your pool is a sign of unbalanced water, not excess chlorine. By testing, shocking, and maintaining proper pool chemistry, you can eliminate chloramines and keep your water clean and odor-free. Regular maintenance, proper filtration, and good swimmer habits will help you enjoy a fresh, healthy swimming environment all season long.