What is Hard Water?

Hard water contains dissolved calcium and magnesium ions. Commonly referred to as "hardness minerals," dissolved calcium and magnesium can cause numerous problems when present in a water supply. Whether it's from a well or a municipal water utility, water usually contains these troublesome elements.

As water falls from the sky in its various forms, it absorbs carbon dioxide in the air and becomes slightly acidic. Water in this weak acid state reaches and enters the ground. Since it is acidic, it absorbs calcium and magnesium, among other things, from the layers of rock through which it passes. The minerals neutralize the water's acidity but also make it hard. Then the water finds its way into larger bodies of water both above and below ground, and eventually into our homes.

How to Recognise Hard Water?

Probably the most recognisable symptoms of hard water are soap scum in the tub and shower, and hard water spots on faucets and fixtures. Hardness minerals react with soaps and detergents to form an insoluble, sticky residue that's difficult to rinse from bathtubs, sinks, faucets and fixtures. The same soap residue is often left on hair, skin and clothing, too. Although not highly visible in these instances, it can cause your skin to dry and itch, and clothing to fade and wear prematurely.

Hard water causes other problems, as well. Over time, scale formed from continuous contact with dissolved minerals in water can collect inside plumbing and on the internal parts of water-using appliances. Service calls to plumbers and repair persons may become necessary as water pressure drops and mechanical parts stop working.

Hard water scale can also coat the inside of a water heater and drastically reduce its heating efficiency. Greater fuel consumption and higher utility bills result when the appliance has to heat water through a layer of rock.

What is Soft Water?

Soft water is essentially free of dissolved calcium or magnesium. A small percentage of homes are supplied with naturally soft water. But since naturally soft water usually has not been neutralized by passing through mineral layers in the ground, it can be quite corrosive. Softening water mechanically, such as with a home water softener, does not make it corrosive, however.

Since calcium and magnesium are not present in soft water, no adverse reaction with soaps and detergents occurs. The result is the virtual elimination of soap scum and the corresponding reduction in time spent cleaning. Hair and skin can "breathe" more readily. And the School of Consumer & Family Sciences at Purdue University recently conducted a study which proved that the life of clothing and household textiles was prolonged up to 15 percent when they were washed in conditioned water.

Soap usage can be dramatically reduced with soft water. Since the water is already soft, the cleaning agents have no hardness minerals to react with and overcome, lather more readily and work more effectively. In fact, a large proportion of the ingredients in most soaps and detergents consist of chemical "water softeners" added to prevent the reaction between the detergent and the hardness minerals present in most water (the reaction that forms a sticky residue or soap curd). Since such chemicals are not necessary for cleaning with soft water, less soap is required. Soft water households experience considerable savings on laundry detergent, dishwashing detergent, bath soap, hand soap, shampoo and many other cleaning products.

Many soft water users purchase pure soaps, products that do not contain additional chemicals or perfumes. These supplies are generally less expensive but clean just as well as (if not better than) their heavily advertised counterparts.

Since soft water contains no scale forming minerals, it leaves the inside of plumbing and water using appliances free of solidified rock. Appliances operate more efficiently and last longer when using soft water. Leading appliance manufacturers have recognised the problems that hard water causes and recommend the use of home water conditioners to help their own products operate more efficiently.

How is Water Softened?

The process of softening water is basically the same for all water softeners:

1. Hard water contains calcium and magnesium ions
2. Water softeners contain resin beads, which hold sodium ions.
3. Hard water passes through the resin beads inside the softener.
4. The beads attract and hold the calcium and magnesium ions, giving off, or exchanging, sodium ions.
5. After the exchange process, the water leaving the softener to the home is soft. Once the resin bed is loaded with calcium and magnesium ions, it must be cleansed (or regenerated) so that it can continue to soften water. Salt water is used to wash the resin beads. The brine solution loosens the hardness ions that have built up on the resin beads. Then the system backwashes and flushes the hardness minerals away. Once again, the resin beads hold sodium ions, and the system is ready to soften more water.

What does it mean when a softener regenerates?

Regeneration is the way a softener cleans its resin bed
Once the resin bed has exchanged all the sodium ions for calcium and magnesium ion, it must be cleansed so that it can continue to soften water A brine solution loosens the calcium and magnesium ions from the resin beads and flushes them to drain. The sodium ions from the brine solution replace the hard water ions on the resin beads so the system is ready to soften more water.