In my home, we get our water from a deep well, and—as is often the case with well water—it’s hard. Ever since I learned how to install a water softener from a local plumber, we’ve had a welcome respite from the problems hard water causes around the house.

What is hard water, you ask? Well, in the simplest terms, it’s water with a high mineral content, but there’s a more precise definition. According to Kelly Russum, a plumber who serves California’s Coachella Valley, water analysts measure hardness in GPG (grains per gallon), where one grain is 64.8 mg. of calcium. “Soft water has GPG lower than 1, and hard water is considered when GPG is 7 or more.” In other words, a gallon of hard water contains half a gram of minerals — usually more.

Water with a high mineral content causes all sorts of problems, including:

• Mineral stains on bathroom fixtures, faucets and other appliances;
• Sediment buildup in water heater tanks;
• Blockages in faucets and plumbing pipes;
• Dry hair, itchy skin and reduced effectiveness of soap.
• Foul-tasting and discolored drinking water. This is primarily caused by iron, which is one of the minerals commonly found in hard water.

You don’t have to get your water from a well to have hard water. Community water in many municipalities is also hard enough to cause mineral stains and make showering unpleasant.

The solution is to install a water softener. Our experts explain what that is, what different types are available and what’s involved with installation and maintenance.

What Is a Water Softener?

A water softener is basically a filter, but unlike one that removes chlorine, pesticides and heavy metals, it’s designed to remove minerals like calcium, magnesium and iron from the water supply. A typical system consists of a cylindrical inflow tank ranging in diameter from eight to 14 inches and in height from 44 to 65 inches and a separate brine tank containing a solution of sodium chloride or potassium chloride.

“There are whole-house water softeners and under-counter water softeners,” advises South Carolina-based plumber Justin Cornforth. “I recommend opting for whole-house systems because they ensure that all appliances in your home and plumbing systems receive softened water.”

How Does a Water Softener Work?

Josh Rubin, a Certified Restorer from Phoenix, AZ, explains the operation of the salt-ion water softener: “It works by removing minerals, primarily calcium and magnesium, from hard water through a process called ion exchange. Put simply, that’s a way to remove and replace the minerals that cause hard water.”

A water softener tank contains a large quantity of resin beads, forming the bed through which water flows into the building. The beads are charged with sodium or potassium ions supplied from the brine tank, and as hard water passes through, the mineral ions are electrically attracted to the beads and displace the sodium or potassium ions, which take their place in the water. “In this process,” says Rudin, “salt is liberated into the water while calcium and magnesium are pulled out.”

The beads eventually become saturated, so the system has to complete a regeneration cycle every week or so. In this cycle, the brine solution is flushed through the tank to restore the salt ions and wash the accumulated minerals down the drain. Most systems do this automatically.