The key to optimum health is balance, including regulating the acid and alkaline balance in the body. Unfortunately our bodies tend to be overly acidic primarily due to diet, stress and even the air we breath. Alkaline water is simply water that registers 7.0 on the pH scale. Below 7.0 pH water is acidic. Ideally the pH of drinking water should be between 7 and 10 and many sources say 8.5 pH as the magic number for perfect balance.