You will never meet absolutely pure water in nature. Coming in contact with other macro-and microelements, it is enriched with various minerals.

Hardness in Water

A low maintenance water purifier is a perfect device to make water in any house softer.

What is Water Hardness?

Water with a high content of salts or minerals is called hard. The main causes of water hardness are dissolved calcium and magnesium (Ca2+ and Mg2+). Rainwater and distilled water are soft, as they include few ions.

Water hardness is formed when water goes through chalk areas or over limestone and magnesium and calcium ions are dissolved into the water:

CaCO3 (s) + CO2 (aq) + H2O (l) ⇋ Ca2+ (aq) + 2HCO3− (aq)

Hardness is shown in terms of the equivalent quantity of calcium carbonate (CaCO3) in milligrams per litre (mg/L) or parts per million (PPM).

There are 2 kinds of water hardness:

  1. Temporary hardness (Carbonate Hardness) – the main reason for it is bicarbonate salts. You can remove it with the help of boiling, that makes the salts decompose into insoluble carbonates, leaving water that is softer upon cooling. The other method is to treat water with calcium hydroxide that has the same effect.
  2. Permanent hardness – caused by sulphate and chloride salts. Its mineral content can’t be eliminated by boiling. It can be removed by chemicals such as water softeners or ion-exchange resins. These salts don’t decompose on heating.

According to the value of total hardness, natural waters are divided into groups:

  • very soft water (0–1.5 mg/l)
  • soft water (1.5–4 mg/l)
  • medium hard water (4–8 mg/l)
  • hard water (8–12 mg/l)
  • very hard water (more than 12 mg/l).
According to standards, the optimal water hardness is 1.0-2.0 mg/l. You may find whether your water hard or not just looking at your kettle. Hard water causes limescale build up on it.

Hard Water Effects

  • The high water hardness leads to a variety of problems like reactions with soaps. Hard water interferes with the lathering properties, due to calcium stearate formation it creates white floc rather but not lathering. So if you wanna wash windows, walls or tiles, hard water and soap combination will leave a film on them. You will also have to use more soap products to get the same effect.
  • It builds up and forms mineral coatings inside pipes leading to water flow and pressure to drop so pipes will need to be replaced.
  • Hard water also damages boiler elements and washing machines reducing water heating efficiency and increasing electricity consumption.
  • If we talk about textile, hard water makes your yarn scratchy after washing. This phenomenon is explained sorption of calcium and magnesium salts of fatty acids, formed during the washing process at the macro level, by the fabric. Hard water also affects the color of the clothes, it leads to the loss of the original color of the fabric: white fabrics get a grayish tint, colored ones become dull.
  • Hard water makes the skin dry while washing.
  • Constant drinking of hard water can cause an imbalance in the body’s mineral balance. Hard water consumption for a long period of time contributes to urinary stones.
  • The taste of natural drinking water, such as spring water, is caused by the presence of hardness salts.
  • The use of hard water for feeding and bathing newborns increases the risk of atopic dermatitis or eczema in children.
  • In combination with soap, hard water forms “soap floc”  that don’t wash off the dirt from the skin, and destroy the natural fatty film that protects from aging and climatic factors, clog pores, causes rash, itching, dryness, dandruff, peeling. The skin is not only ages faster but also becomes sensitive to irritation and allergic reactions.
  • Calcium and magnesium salts, combining with proteins that we get from food, settle on the walls of the stomach and intestines, complicating their motility, causing dysbiosis, disrupt enzymes and ultimately poison the body. The constant use of water with high hardness leads to a decrease in gastric motility and the accumulation of salts in the body.
  • The water with lots of calcium and magnesium ions hurts the cardiovascular system.
  • Long use of hard water leads to joint diseases (arthritis, polyarthritis), the formation of stones in the kidneys and biliary tract.
  • Some products (for example, meat and legumes) boil much longer in hard water since calcium ions form insoluble compounds with food proteins;
  • Hard water with a high content of calcium and magnesium spoils not only the color but also the taste of tea and coffee;
  • Washing the head with hard water contributes to dry hair, dandruff, skin diseases and, ultimately, loss of a certain amount of hair;

How You Can Soften Water

There are 2 ways to soften water:

  1. A water softener. Hard water goes through a resin bed. The magnesium and calcium are exchanged for anions like sodium. You must regenerate resin with the help of salt as it reaches its exchange capacity.
  2. Reverse Osmosis systems. The hard water goes through a semi-permeable membrane under pressure and leaves the hardness behind. With the salts of hardness, most of the other salts are removed. The cleaning efficiency can reach 99.9%. Don’t forget to replace the filters from time to time.

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About the Author

Joshua Howard

I'm a healthy living blogger who loves to help people who care about having an eco-friendly home environment and a healthy lifestyle. With proper nutrition I helped my brother to cure gastritis and my father to normalize his blood pressure.

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