
How to Fix Total Hardness in Pool
A Step-by-Step Guide to Balancing Your Pool's Water
Fixing total hardness in your pool is essential for maintaining water quality and ensuring a safe swimming environment. Total hardness refers to the concentration of calcium and magnesium in your pool water. If the hardness levels are too high or too low, it can lead to various issues, including scaling, cloudy water, and skin irritation. In this guide, we will walk you through the steps to effectively adjust the total hardness in your pool, ensuring crystal clear water and a pleasant swimming experience.
Understanding Total Hardness in Pools
Total hardness is a crucial aspect of pool water chemistry. It is measured in parts per million (ppm) and is vital for preventing corrosion and scaling in your pool system. The ideal range for total hardness in swimming pools is between 200-400 ppm. If your pool's hardness is outside this range, you may need to take corrective actions.
Step-by-Step Guide to Fix Total Hardness
- Test Your Pool Water: Use a reliable water testing kit to measure the total hardness level in your pool. This will help you determine whether you need to increase or decrease the hardness.
- Gather Necessary Tools: You will need the following materials:
- calcium chloride (for raising hardness)
- sodium carbonate (for lowering hardness)
- Water testing kit
- Pool brush
- Bucket
- Add Calcium Chloride: If your total hardness is below 200 ppm, add calcium chloride to increase the hardness. Follow the manufacturer's instructions for the correct dosage based on your pool size.
- Lower Hardness with Sodium Carbonate: If the hardness is above 400 ppm, you can lower it by diluting the pool water. This can be done by draining a portion of the water and refilling it with fresh water. Additionally, you can use sodium carbonate as directed.
- Retest Water: After making adjustments, retest the water to ensure that the total hardness is within the ideal range.
Safety Notes
Warning
- Always wear gloves and goggles when handling pool chemicals.
- Ensure proper ventilation when adding chemicals.
- Store chemicals in a cool, dry place away from children and pets.
Troubleshooting Common Issues
If you notice persistent issues with your pool's hardness levels, consider the following troubleshooting tips:
- Check for leaks in your pool that may be causing dilution.
- Inspect your water source; high mineral content in fill water can affect hardness.
- Regularly clean your pool and maintain proper filtration to prevent buildup.
Quick Facts
Quick Facts
Key Takeaways
- Regular testing of pool water is essential for maintaining proper hardness levels.
- Calcium chloride is used to increase hardness, while sodium carbonate can help lower it.
- Always follow safety precautions when handling pool chemicals.
- Regular maintenance and cleaning of your pool can prevent hardness issues.
FAQs
- What happens if my pool's hardness is too low?
Low hardness can lead to corrosion of pool surfaces and equipment. - Can I use baking soda to adjust hardness?
Baking soda primarily affects alkalinity, not hardness. - How often should I test my pool water?
It's recommended to test at least once a week during swimming season.

Jaden Bohman is a researcher led writer and editor focused on productivity, technology, and evidence based workflows. Jaden blends academic rigor with real world testing to deliver clear, actionable advice readers can trust.
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