Reference Electrode Filling Solution Read the instructions that came with your electrodes carefully. We use 4M KCl solutions only. However, the most common filling solution for combination electrodes is 4 M KCl saturated with AgCl. Permanently filled or Gel electrodes Due to their unique micropore junction, it is recommended that they be stored hanging dry. If your electrode exhibits slow response, poor span between two buffer values or undue sensitivity to movement of the electrode, rejuvenation may be necessary to improve performance.
Response varies with the electrode and the solution it is in.
Generally working electrodes reach 0.05 pH units of the final reading in buffer within 10 seconds. Without moving the slope dial, read a pH 4 buffer. If your electrode exhibits either of the above problems or is sensitive to movement, rejuvenation is in order. To treat, simply dip the bulb into the acid and immediately into the base. Repeat this several times.