The Langelier Saturation Index, developed by Dr. Wilfred Langelier in 1936, is the best tool we have for assessing the saturation of calcium carbonate in water and maintaining balanced water chemistry.

The LSI formula incorporates calcium hardness, water temperature, pH, alkalinity, cyanuric acid, and total dissolved solids. Perfectly balanced, neutral water has an LSI of 0.0, but water within a range between -0.3 and +0.3 is safe for swimmers and their fiberglass pool shells.

Water with an LSI above +0.3 will lead to scale formation, while water registering below -0.3 can aggressively deteriorate the gel coat and cause chalking damage.

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The FAQs provided above offer general guidance on fiberglass pool care. However, proper pool care involves various factors such as water chemistry, equipment maintenance, safety measures, and compliance with local regulations. It is crucial to consult a qualified pool professional or refer to your equipment and/or pool manufacturer’s owner’s manual for comprehensive information. Neglecting critical aspects of pool care can lead to water quality issues, equipment/pool damage, safety hazards, and potential legal implications. This information should be considered supplementary and not a substitute for expert guidance.