Typically, bottled water is processed to remove certain contaminants and may have additives to improve flavor. The mineral content in this water usually is not modified by the manufacturer and it may contain from 1,000 to 3,000 parts per million total dissolved minerals. Seltzer water is filtered tap water which has been treated with carbon dioxide gas. It has a much lower mineral level than club soda. It is becoming a favorite for those who want a non-alcoholic drink.
Drinking water is usually from a public water supply.
It often has been treated to remove minerals. Some have a few minerals added back for improved flavor. Drinking water is carefully disinfected, usually by ozonation, to remove unwanted bacteria prior to bottling. Natural water is bottled spring, artesian or well water that is unmodified by mineral addition or deletion. However, natural water usually is filtered and ozonated prior to bottling.