You have probably heard of hard water and freshwater. The difference between the two comes from the limestone levels they contain: hard water is the one that has a greater amount of limestone while freshwater has less. It is called hard water when it contains a high level of minerals, specifically magnesium and calcium salts. These waters are usually subterranean soils of limestone, which increases the levels of limestone and magnesium, among others. Hard water also leaves more residues, for example, limestone on the drains and pipes, causing problems in the house. For this reason, in geographical areas with hard water, it is recommended to use products that avoid the formation of limestone.