Water is the basic necessity of life. Water is classified as hard water and soft water based on its chemical content. The hardness of water depends on its calcium content, which is measured in parts per million. If the calcium content of the water is 160 ppm or less, it is referred to as soft water, and if the same is above 160 ppm, then it is hard water.
The simplest definition of hard water would be water with high mineral content. These include calcium, magnesium, chalk, lime, etc. which get dissolved into the water making its way through the ground. Among these, calcium and magnesium are found in abundance.
Hard water may also include other compounds such as bi-carbonates and sulfates. It is generally preferred as drinking water owing to its high mineral content. Even in terms of taste, it is superior to soft water.
Soft water is the water which contains very few or absolutely no traces of minerals. Among the ground water sources, soft water is generally derived from igneous rocks, such as granite, or sedimentary rocks, such as sandstone, which are themselves low in mineral content. Extremely hard water can also be harmful for the plumbing system.
Soft Water can also be derived by getting rid of all the minerals in the hard water using a water softener system. In terms of taste, it is relatively salty and sometimes, not at all suitable to drink. In such a scenario, this water has to be subjected to hardness correction or has to be blended with hard water to make it potable.
Hard Water Vs. Soft Water
One of the most prominent differences between hard and soft water is that the former doesn't work well with soap, while the latter does. The ions dissolved in hard water react with the chemicals in soap and produce an insoluble residue which is difficult to wash away, while soft water and soap work very well together and make the skin smooth and glowing.
A report by the National Research Council in 1980s stated that the high mineral content of hard water makes it an important source of minerals and gives it an edge over soft water. However, there are researchers who believe that soft water has an edge over hard water, as it saves money by increasing the cleaning efficiency by more than 200 percent.
There is no definite winner in this comparison, as the end result by and large depends on what you are used to. People who have been using hard water all the while are bound to feel strange with the smooth and glowing skin attributed to soft water while people used to soft water are bound to feel that hard water tastes a bit weird.