Water softening systems should be installed only when necessary. They are effective in removing calcium and magnesium, which cause water hardness. Water that has in excess of 150 milligrams per liter hardness can create scale buildup in hot water pipes and other plumbing fixtures, and can also inhibit effective cleaning with soaps and detergents. Water softeners are also able to remove excessive iron, which has no adverse health effects but can affect taste, color, or odor.

Water softener units are usually connected directly to the water supply line. A separate faucet may be installed for unsoftened water for drinking and cooking.

How they work
Most units work through ion exchange, by means of a synthetic resin that attracts calcium, magnesium, and other metal atoms, and which is saturated in a salt solution. Sodium ions exchange with the calcium and magnesium ions as water passes through the system, making the water soft. The resin must be recharged (regenerated) once it is completely filled with the hard ions.

The softened water is consequently saltier, which can be a health concern for some individuals, and can be more corrosive to pipes than hard water. Instead of using sodium as the exchange medium, some newer models of water softener use potassium chloride, which is not harmful to plants.

Types of units
Unit types are distinguished by the manner in which they are recharged: automatically, semi-automatically, or manually.

Automatic softeners usually initiate regeneration by means of a time clock, but some are started by controls set to regenerate after a particular number of gallons have been softened, or by activation of a meter that detects hardness. Manual units require the user to operate control valves for backwashing, brining, and rinsing. Semi-automatic softening systems are fully automatic except for the start of regeneration.

Tips for conserving water

• Run the minimum number of regenerations needed to maintain softness. Manual units can be adjusted to increase the time between backwashing sessions, thus saving water. Units with demand-initiated regeneration cycles and units that are controlled manually are the most cost-effective and water-efficient systems to use. Newer models generally require less water in the regeneration process and also less salt.



• Consider using a non-regenerating water filter as an alternative to a water softener.



• Turn off the softener when you are on vacation.