LSI calculator for pool service
Calculate Langelier Saturation Index from your readings. Enter values, get a verdict and recommended adjustments. Tabulated factors, CYA correction included.
Readings
Carbonate alkalinity = total alkalinity minus (CYA / 3). Pooly does this correction automatically. Used in the alkalinity factor lookup.
Result
Balanced, ideal
Recommended actions
- Maintain current chemistry.
- Re test next visit.
Pooly auto calcs LSI on every visit
Recommendations come with each reading, no manual lookup.
About this calculator
What LSI tells you
The Langelier Saturation Index estimates whether your pool water is scaling, balanced, or corrosive based on six readings. Numbers above zero trend toward scale on tile, heater elements, and salt cells. Numbers below zero trend toward etching of plaster and corrosion of metal fittings.
Pool service operators target an LSI between minus 0.3 and 0.0. Pooly auto calcs this on every visit and recommends dosing to move readings into the band, no manual lookup needed.
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