pH and carbon dioxide
The measure which indicates whether water is acidic or basic is known as pH. More precisely, pH indicates the hydrogen ion concen¬tration in water and is defined as the negative logarithm of the molar hydrogen ion concentration (-log [H+]). Water is considered acidic when pH is below 7 and basic when pH is above 7. Most pH values encountered fall be¬tween O and 14. The recom¬mended pH range for aquaculture is 6.5 to 9.0 (Figure 1).