The Langelier Saturation Index (LSI) is a calculation used to determine whether your hot tub or swim spa water is properly balanced and whether it may be prone to scaling or corrosion.
If the result is between -0.5 and 0.5, the water is balanced.
If it is below -0.5 or over 0.5, your water is either over or under saturated, which can lead to problems. Add the necessary adjustment products to bring your Total Alkalinity, pH and Total Hardness within the proper standards, then retest.
Ideal Water Balance Levels:
- Total Alkalinity: 80 – 120 ppm
- pH: 7.2 – 7.6
- Total Hardness: 150 – 250 ppm
Determine Your Water’s Langelier Saturation Index
Test the water for pH, Alkalinity, Calcium Hardness and Temperature. Then, enter the information below.
