Water quality can be important for the health of your plants. Depending on where your water comes from, it likely contains many natural salts that are found in regular tap water. These salts give water their taste, and can also affect how much room there is left in the water for fertilizers. There are many ways to measure these salts, and in my opinion the easiest and most universal is electroconductivity. Electroconductivity, or E.C. is the ability of water to conduct electricity.