How Do I Balance pH and Alkalinity in My Pool?

Adjust alkalinity first using sodium bicarbonate, then fine-tune the pH with a pH increaser or decreaser.

Why pH and Alkalinity Matter

pH Level

The pH scale measures how acidic or basic your pool water is. The ideal range for pool water is 7.4 to 7.6. If pH is too low, the water becomes acidic, which can cause skin and eye irritation, corrode pool surfaces, and damage equipment. If pH is too high, chlorine becomes less effective, leading to algae growth and cloudy water.

Alkalinity

Total alkalinity helps stabilize pH levels, preventing sudden fluctuations. The recommended range for alkalinity is 80 to 120 parts per million (ppm). When alkalinity is too low, pH levels can swing unpredictably, making pool maintenance difficult. If alkalinity is too high, it can lead to cloudy water and scaling on pool surfaces.

How to Test pH and Alkalinity

Regular testing ensures that your pool stays within the ideal ranges. Follow these steps to test your water:

1. Use a Pool Test Kit: Choose between test strips or a liquid test kit.
   

2. Collect a Water Sample: Take water from about 12–18 inches below the surface.
   

3. Check pH Levels: Compare the color change to the provided chart.
   

4. Test Alkalinity: Follow kit instructions to determine total alkalinity.
   

5. Record Results: Keeping track of levels over time can help detect patterns.
   

Testing at least two to three times a week is recommended, especially during hot weather or after heavy pool use.

How to Lower pH and Alkalinity

If your pool’s pH or alkalinity levels are too high, you will need to lower them to restore balance.

1. Use Muriatic Acid or Dry Acid

• Muriatic Acid (liquid) is more effective but requires careful handling.
  

• Sodium Bisulfate (dry acid) is easier to use but takes longer to dissolve.
  

2. Follow These Steps:

1. Determine the Required Amount: Use a dosage chart to avoid overcorrection.
   

2. Dilute If Necessary: Always add acid to water, never the reverse.
   

3. Pour Slowly: Distribute evenly around the deep end of the pool.
   

4. Wait and Retest: Allow water to circulate for 4–6 hours before checking levels.
   

If pH is still too high, repeat in small increments until the desired level is reached.

How to Raise pH and Alkalinity

When levels are too low, your pool water may become corrosive, affecting pool surfaces and irritating swimmers.

1. Use Baking Soda or Soda Ash

• Baking Soda (Sodium Bicarbonate) raises alkalinity with a slight effect on pH.
  

• Soda Ash (Sodium Carbonate) raises pH more effectively but also increases alkalinity.
  

2. Follow These Steps:

1. Measure the Needed Amount: Use a pool chemical calculator.
   

2. Pre-Dissolve If Needed: This ensures even distribution.
   

3. Add to the Deep End: Pour in slowly while the pump is running.
   

4. Allow Circulation: Run the pump for 6–8 hours before retesting.
   

If alkalinity is too low but pH is balanced, add baking soda. If both are low, soda ash is the better choice.

Common Mistakes to Avoid

Even experienced pool owners can make mistakes when balancing water chemistry. Here are some of the most common errors:

• Adding Too Much at Once: Small adjustments are better than drastic corrections.
  

• Not Waiting Before Retesting: Water needs time to circulate before showing accurate levels.
  

• Adjusting pH Before Alkalinity: Always fix alkalinity first since it stabilizes pH.
  

• Using the Wrong Chemicals: Make sure you’re using the right product for the needed correction.
  

• Neglecting Regular Testing: Skipping tests can lead to severe imbalances that are harder to fix.
  

Tips for Maintaining Balanced Water Chemistry

Keeping your pool’s pH and alkalinity stable requires regular maintenance and monitoring. Follow these best practices:

• Test water at least twice a week.
  

• Keep alkalinity between 80–120 ppm.
  

• Maintain pH levels at 7.4–7.6.
  

• Add chemicals in small amounts to prevent overcorrection.
  

• Run your pool filter daily to help distribute chemicals evenly.
  

• Keep a maintenance log to track chemical adjustments.
  

Balancing your pool’s pH and alkalinity ensures clear, clean water and prevents damage to your pool and equipment. With regular testing and the right techniques, maintaining ideal water chemistry becomes simple and hassle-free.