3. Water & Environmental / Water Analysers

How can I measure the Langlier Saturation Index (LSI) of water samples?

The Langlier (or Langelier) Saturation Index, LSI, of water indicates whether hard water will precipitate Calcium Carbonate deposits, dissolve Calcium Carbonate or be in equilibrium based on it’s pH value and the saturation pH.

1200px-Hard_Water_Calcification
Hard water holding Calcium Carbonate and other minerals can deposit these as solids when the LSI value is low – as seen on this tap

Previously this test has been quite onerous, with a manual test followed by a series of calculations.

The eXact iDip photometer now offers this test built in, cutting out the long manual calculations and making the test fast and simple.

Using a smart phone as the brains of the device allows the eXact iDip photometer to be upgraded and updated constantly, via the app interface.

eXact iDip photometer
eXact iDip photometer

The latest addition is the ability to determine LSI and magnesium hardness without doing any written calculations.

The device uses data collected by simple tests on the photometer and performs the calculations for you, displaying the values on both the photometer and the app. Since the calculations are in the app rather than the photometer, if you already have an eXact iDip unit you will just need to update the app on your smart phone to get this new feature.

To find out more about the eXact iDip photometer and the other water quality tests it can perform, simply follow the links above or contact us if you have any questions;


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