Calcium and magnesium levels combine to determine the mineral water’s “hardness”. Bottled water is naturally soft, thanks to low levels of calcium and magnesium. Higher levels are often found in municipal water, which is often “softened”—particularly in the United States—to be used at home. The taste of water is impacted heavily by softening.

Hard Water

Hard tap water makes cleaning more difficult and more dependent on soaps and synthetic detergents. Scaling in boilers and teakettles comes from hard water. But hard water does not pose any danger to your health: According to the U.S. National Research Council, the magupnesium and calcium in hard water can actually contribute to your daily dietary requirements.

Soft Water

Water is softened with an ion-exchange water softener, which adds sodium (salt) to the water. About 8 mg/l of sodium are added for every grain of hardness (17.1 mg/l) taken out. Water softening accustoms most Americans to slightly salty water. In the United States, water hardness is not regulated by the Environmental Protection Agency. Instead the Department of the Interior and the international Water Quality Association offer the following classifications:

Soft 0 - 17.1 mg/l
Slightly Hard 17.1 - 60mg/l
Moderately Hard 60 -120mg/l
Hard 120 -180mg/l
Very Hard 180mg/l & over

Hardness can be calculated with this formula (calcium and magnesium should be measured in milligrams per liter): HARDNESS = (calcium x 2.5) + (magnesium x 4)

  • In The News
  • History of Bottled Water
Over the past two decades, bottled water has become the fastest-growing drinks market in the world. The global market was valued at $157bn in 2013 and is expected to reach $280bn by 2020.
Water is turning into wine. The same culture that surrounds the production and consumption of wine is emerging around water. Water competitions akin to wine competitions are now held.
NY Times Science
Earth is old. The sun is old. But do you know what may be even older than both? Water.
Salt Science
Washington Post declares that unknown to many shoppers urged to buy foods that are “low sodium” and “low salt,” this longstanding warning has come under assault by scientists who say that typical American salt consumption is without risk.

History Bottled Water
Ours is the blue planet, and the hallmark of life on Earth is water. But where did this colorless, odorless liquid first come from? Recent discoveries in astrophysics suggest that water is not native to Earth.
History Bottled Water
This website appeared first in 2004 and the concept of considering water at the same level as wine and food as a natural product was still new and foreign to many.