A pH meter is good tool for check water quality. It tell you how acid or basic the water are. pH scale go from 0 to 14, where 7 neutral. If pH below 7, water is acidic, and above 7 it basic. Knowing pH of water is crucial for many reason. For example it affect fish and plants in ponds or aquariums. Also help in agriculture, right pH make crops grow better. So using pH meter can keep your water helthy and safe.