Alkalinity measures the waters ability to resist changes in pH it does not refer to or measure the pH. A measure of alkalinity in our case (SW
) is the total carbonate and bicarbonate in the water. Which in turn is KH
and the same as alkalinity, ie... dKH
is the measure of calcium and magnesium combined in the water and a useless measure in terms of SW
chemistry. In order for these two elements to make sense they must be quantified seperately.