Whats the deal with water hardness and why is my pH so high?
In some regions of the country, the water supply is in close contact with limestone. These regions have “hard water” which typically has high pH (greater than 7.8). There are two things at work here. Limestone is mostly calcium carbonate (CaCO3) which slowly dissolves in water and dissociates into Ca++ and CO3– (calcium and carbonate ions). The calcium ions (Ca++) contribute to general hardness, abbreviated GH. Magnesium ions (Mg++) are the other component of general hardness. GH does not affect pH but is the type of hardness that biologically affects organisms. Calcium is used in the walls of cells and a lack of calcium can cause both plant and animal deformities. If a plant or fish is said to prefer hard or soft water, it is “general hardness” that is being discussed. The carbonate ions (CO3–) are a component of alkalinity, also known as acid buffering or carbonate hardness (KH). KH measures carbonate and bicarbonate ions and is the predominant component of alkalinity. In general,
