Electrolyte Solution 3.5M KCl (230 mL)HI7082M is a pH and ORP electrode fill solution that contains 3. 5M KCl, which is specifically produced for double junction electrodes. The electrolyte level in refillable electrodes should be checked before performing any measurements. If the level is low, refill with the proper electrolyte solution to ensure optimum performance. This simple maintenance helps guarantee adequate head pressure to promote the flow of reference electrolyte into the