Water hardness is the amount of dissolved calcium and magnesium in the water. Can it be felt? Yes.
If hands feel soapy when washed with soap even after using a lot of water to wash the soap off, the water contains high calcium levels. If dishes have spots or films of dust-like substance after washing, then it is the dried minerals from hard water. If solid deposits form when water is boiled, then it is calcium carbonate. If it is any of the above-mentioned cases, then more soap is needed to do anything like washing hands, taking a bath, or doing laundry. Humans need calcium and magnesium to live a healthy life, but too much of anything can be life-threatening, and that is why lab water testing is crucial. Also, too much of these minerals in water can lower efficiency and reduce the lifetime and increase the energy consumption of house appliances such as heaters and pipes, etc.
Water hardness is measured by determining how many parts per million (ppm) of calcium and magnesium ions are present or how many milligrams of (Ca) per liter (1L) of water. Water containing calcium carbonate above 121 mg/L is termed hard. It is essential to know the hardness level of water one uses every day.
Here are four ways to measure water hardness:
- The simplest and the most common method is the soap test. This test is to infer whether water is soft or hard. Soft water, when vigorously mixed with soap, forms foam. But hard water, when vigorously mixed with soap, forms a cloudy solution. Take 350 ml of water in a clear glass bottle. Add ten drops of dishwashing liquid. Close the lid of the glass bottle and vigorously shake it. The formation of foam confirms the sample is soft water, and the formation of cloudy liquid and studs confirms that it is hard water.
- The second method is to get test strips from hardware stores or online. The test kit has paper-like strips, a color chart to measure the hardness of the water. Take the water to be tested in a cup. Take a strip in hand and be aware not to hold the end which has the colored pad. Dip the strip for one second into the cup. Gently tap the paper strip on the rim of the cup to shake off excess water. Place the strip with the pad side up. Allow the color to develop for 30 seconds. Then immediately compare the test pad to the color chart. Find the closest color match within two minutes. One strip can only be used once.
- The third method is to use a testing meter. This can be bought online. Take a glass of water. Turn on the device. Remove the cap and immerse the measuring end of the testing meter into it. Note down the reading on display. Compare it with the color chart given in the device to check the water hardness level.
- However, the methods mentioned above are seldom accurate. The best way to measure water’s hardness precisely is to get water samples tested by certified companies.
Types of water hardness:
There are two types of hardness:
- Temporary hardness or “Carbonate hardness”: This refers to the presence of carbonates and bicarbonates of calcium and magnesium in the water. This can be removed by heating the water or making it react with lime. Magnesium hydroxide and calcium carbonate form as precipitate, and CO2 escapes as a gas.
- Permanent hardness or “non-carbonate hardness”: This refers to the presence of sulfates, chlorides, and nitrates of calcium or magnesium in the water. Depending on the water’s chemical composition, this can be removed by using lime or lime with soda ash.
Hard water minerals consumed in high quantities can have detrimental effects. Excess calcium can interact with other minerals such as iron, zinc, magnesium, and phosphorus within the intestine and reduce these minerals’ absorption. Excess magnesium salts can cause changes in bowel habits such as diarrhea. Higher concentrations of sulfate and magnesium can cause laxative effects.
Hard water also influences cardiovascular diseases, malfunctioning of the central nervous system, Alzheimer’s disease, diabetes, kidney stones, reproductive health, bone mineral density. It can also cause cancer associated with various organs such as gastric cancer, colon cancer, rectal cancer, pancreatic cancer, esophageal cancer, ovarian cancer, haptic cancer, etc. So, one should never take the hardness of the water lightly. Whether one consumes municipal water or groundwater, it is crucial to do lab water testing.