About The Illinois State Water Survey

Water Softeners

Water Softeners contain an ion exchange resin that exchanges sodium ions (Na+) for calcium (Ca++) and Magnesium (Mg++) ions. When the sodium is depleted, the resin needs to be regenerated. This is done by backflushing the resin with a concentrated salt (sodium chloride) solution. Sodium ions displace the calcium and magnesium ions, which are washed down the drain, and the resin is ready for another softening cycle.

how water softeners work

Illinois State Water Survey

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Champaign, IL 61820-7463
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