The hardness of water is the amount of minerals dissolved in it. If the amount of dissolved minerals is high-the water is hard, if low-then soft.
Water hardness increases when filtered through porous rocks such as chalk or limestone. Signs of high rigidity is the formation of lime plaque on pipes, taps and inside kettles, as well as the formation of foam on the water when adding soap. Hard water is found in areas such as lake Malawi, where fish are adapted to high hardness and pH levels.
Limescale and soap suds do not form in soft water. Soft water flows over hard rocks, such as granite, or through fallen leaves and peat, from which minerals are almost not washed away. Continue reading