Expert Verified Updated: March 2026

Hardness (Total to Calcium) Converter

Estimate calcium hardness from your total hardness test result.

Quick Conclusion
The Hardness (Total to Calcium) Converter provides instant dose calculations for pool maintenance, helping you maintain perfect water balance and extend equipment life.

Technical Comparison

SourceAvg TotalCalcium Fraction
City Water100-300~75%
Well Water400-800~60%
Softened< 50~90%

Scale Prevention

Magnesium rarely causes scaling in pools, so knowing the calcium fraction is key for LSI calculations.

Actionable Steps

Total vs Calcium

Total hardness includes Calcium and Magnesium. Most pool problems are caused specifically by Calcium.

⚠️

Safety Warning: High total hardness might be okay if calcium is low, but usually both rise together.

Pro-Tip

If your total hardness is very high but your calcium is balanced, you don't need to worry about scaling. It's the Calcium (Ca2+) that forms the hard white crust on your tiles.

Frequently Asked Questions

Why 25%?

Magnesium typically makes up 20-30% of total hardness in tap water.

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