Expert Verified Updated: March 2026

Calcium Hardness Increaser Calculator

Prevent pool floor etching and equipment corrosion. Calculate the exact dose of Calcium Chloride needed to reach the ideal hardness level.

Quick Conclusion
To raise Calcium Hardness by 10 ppm in a 10,000-gallon pool, use 1.25 lbs of Calcium Chloride (77% strength). Ideal range for plaster pools is 250-400 ppm.

Technical Comparison

Surface Type Ideal Range Risk of Low Calcium
Plaster / Gunite 250-450 ppm Severe Etching & Staining
Vinyl / Fiberglass 175-225 ppm Metal Corrosion
Concrete Tile 200-400 ppm Grout Failure

Actionable Steps

Pro-Tip

Exothermic Reaction: When adding Large amounts of Calcium Chloride, do it in stages. The heat generated can actually melt cheap plastic buckets if you add too much at once. Safety glasses are a must!

Frequently Asked Questions

Ideal range?

For plaster pools, 250-450 ppm is ideal.

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