Calcium hardness calculator
PROCalcium chloride to raise calcium hardness.
Short answer: lb ≈ (gal/10k) × (ΔCH/10) × 1.25. 20,000 gal, +100 ppm CH = 25 lb calcium chloride. Enter your measurements above and the calcium hardness calculator returns the quantity, unit conversions and an estimated cost instantly, in imperial or metric — no sign-up needed.
What do you need to measure?
What is the answer?
Calcium chloride
25.00 lb
+100 ppm CH
How does the calcium hardness calculator work?
lb ≈ (gal/10k) × (ΔCH/10) × 1.25.
What does a worked example look like?
20,000 gal, +100 ppm CH = 25 lb calcium chloride.
What do people ask most?
›Target CH?
200–400 ppm for plaster pools; 150–250 for vinyl/fiberglass.
Which pool calculator should you use next?
Where can you learn more?
Read field notes on estimating and materials, or browse every calculator we make.
What should you read before you order materials?
Field notes from real jobs that explain the numbers behind this calculator.
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