What is Hard Water?

Oct. 21, 2021

What is hard water & how can it be managed?

About the author:

Brian Campbell founder for WaterFilterGuru.com. Campbell can be reached at [email protected].

What is Hard Water?

Water hardness is a measure of how many "hard" calcium and magnesium minerals are present. Hard water contains a high concentration of these minerals. Soft water, on the other hand, contains little-to-no hardness minerals.

RELATED: What is Water Softening?

How Does Water Become Hard?

Calcium and magnesium are natural minerals found in rocks and soils all over the world. Most of our drinking water comes from groundwater - i.e. rainwater that has seeped into the ground, filling underground aquifers.

When water passes through layers of rock and soil, it picks up some of the ground's mineral content, including calcium and magnesium.

The amount of calcium and magnesium that enters groundwater depends on the geology of the area. Generally, the more mineral-rich rocks and soils in the area, the harder the local water will be.

What Are the Signs of Hard Water?

If you have hard water in your home, you'll probably know about it. The signs of hard water include the following: 

Limescale on Showerheads, Sinks and Bathtubs

Limescale is the most noticeable sign of hard water. This white, rough substance can build up around your faucets, on your showerhead, and in your sinks and bathtubs.

White Spots on Glassware and Dishes

Calcium and magnesium minerals can also cause white, milky spotting on dishes and glassware. It can be difficult to remove these stains when using hard water for washing.

Soap Scum on Hands

Hard water can also produce a filmy layer that sits on your skin and hair, known as soap scum. This is caused by the soap reacting to the calcium in the water. 

Loss of Water Pressure

The limescale produced by hard water can build up inside pipes and plumbing and slow down water flow. This can result in a loss of water pressure, which may affect the flow of water from faucets and showerheads.  

Mineral Water Taste

Calcium and magnesium give water an alkaline mineral taste. If your water has a similar flavor to bottled mineral water, it probably has a high magnesium and calcium content. 

What Are the Effects of Hard Water?

Inefficient Appliances 

A major problem caused by hard water is inefficient appliances. Your dishwasher and washing machine will need more soap to do the same job, and your heater will take longer to heat up, as the limescale inside the system will act as a layer of insulation.

Dry Skin and Hair

If you shower in hard water, you may experience dry skin issues, and your hair may be brittle and lacking moisture. Hard water also makes it more difficult to lather soap, so you'll end up using skincare and haircare products faster than you should.

More Cleaning Required

Hard water scale can be very difficult to remove, and can build up quickly even after you've cleaned it away. You'll need to clean harder and for longer if your home uses hard water.

Faded Clothes

Hard water works much faster to strip color from clothes than soft water. You may notice that your clothes feel scratchy, too, because of the additional minerals present. 

Are There Any Regulations For Water Hardness in Tap Water?

Water hardness doesn't pose any major health risks. In fact, calcium and magnesium are needed for many functions in the human body, and we obtain these minerals in our diets as well as in our water. 

For this reason, there are no regulations for water hardness in tap water. Hardness minerals don't get removed in treatment facilities, and this is why water hardness can vary so much from state to state, depending on the area's geology.

Although there are no hard water regulations, there are still hard water measurements that can be referred to when determining water hardness. 

Generally, water containing between 0 and 60 mg/L of calcium and magnesium is considered soft. Water containing up to 120 mg/L is classed as moderately hard, while water with up to 180mg/L of hardness is classed as hard. If water contains any more than 180mg/L of hardness, it is considered very hard.

What Are the Treatment Options for Hard Water?

To treat water hardness, there are several systems available. The most popular treatment options are ion exchange water softeners, saltless water conditioners, and electronic/magnetic descalers. 

Ion Exchange Softening

Ion exchange water softeners consist of two tanks: a brine tank and a resin tank. The brine tank contains sodium, which is sent into the resin tank. 

When a water supply flows through the resin tank, the calcium and magnesium minerals are attracted to the resin. They’re pulled from water, and stick to the resin beads, while equal amounts of sodium ions are released into the water.

The resin will eventually become saturated with calcium and magnesium and depleted of sodium. When this happens, the softener will regenerate, flushing out the hardness minerals and replenishing the media with sodium.

Water Conditioning

Water conditioners use a crystallization method, such as template-assisted crystallization, to prevent hardness minerals from forming scale. 

These systems typically use a single tank containing a conditioning media. When water flows through this media, the calcium and magnesium are crystallized into insoluble microcrystals, and form hard outer edges. 

This method of water treatment doesn’t technically soften water, as the minerals are still present. However, it will alter the calcium and magnesium, preventing them from being able to stick to surfaces as limescale.  

Electronic/Magnetic Descaling

Magnetic or electronic descaling is the most affordable hard water treatment option. 

There are no tanks, media or resin involved in electronic/magnetic descaling. Instead, the system consists of magnets or wires that are placed around a point of entry water supply line. These wires or magnets release an electromagnetic field that changes the way calcium and magnesium minerals behave in water, preventing them from forming scale. 

There isn’t much evidence to prove the efficacy of electronic or magnetic descaling at the moment, though you can find many reviews from customers online who claim to have noticed a difference in scale formation in their homes.

About the Author

Brian Campbell

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