pH is a measurement of the acidity of water. It is very important because even small changes in pH can have detrimental effects on the chemistry of marine organisms and the solubility of inorganic substances such as metals. For example, acidic waters reduce the ability of animals with a hard calcium skeleton (corals and oysters) to absorb calcium. Waters with high acidity can also affect the survival rate of eggs in an estuary. pH is measured in pH standard units, ranging from 1-12, with 1 being acidic, and 12 being basic. Pure water has a pH of 7.0, which is neutral. Most animals need a pH range from 5-9.
The normal range of pH in Galveston Bay is 7.7-8.5.
This is the instrument Artist Boat students use to test pH levels: