Fountain solutions contain buffering agents that keep the fountain solution pH in a predetermined range. Conductivity measures all the ions that conduct electricity and is the preferred method to monitor fountain solution. We recommend using both and here's why. Although not a common occurrence, we have seen situations in which contamination was introduced into fresh fountain solution with little etch added and yet the conductivity reading was still correct. The pH, however, was much more alkaline than normal, and was the clue that something was drastically wrong. When mixing fresh fountain solution, measure and record both the conductivity and pH. These numbers become your benchmark for new fountain solution. Measure the fountain solution daily, record the pH and conductivity numbers. Note the readings when you change the old fountain solution and mix a fresh batch. The difference in the first and last reading is the normal conductivity and pH range for your fountain solution. If at any time the conductivity and pH outside of this range something is wrong with the fountain solution. Remixing fresh fountain solution can be a simple fix for more complicated press problems.