To ensure a quick response and free-flowing liquid junction, the sensing element and reference junction must not be allowed to dry out.  The following instructions apply to refillable electrodes.  For gel-filled electrodes, consult instruction manual.

Soak electrode in a pH Electrode Storage Solution.  If a storage solution is unavailable, pH 4 buffer or 0.1 M KCl may be used.  The fill hole should be covered to prohibit evaporation of reference fill solution.

Cover sensing element with its protective cap containing a several drops of pH/ORP storage solution.
NOTE: Before returning to use, rinse well with deionized water, refill with appropriate fill solution and soak in pH 4 buffer for 1-2 hours.

Cleaning your electrode between and after use will help extend the life of your electrode and avoid the cost of early replacement.

General - Soak electrode in 0.1 M HCl or HNO3 for half an hour, followed by soaking it in storage solution for at least two hours.

Reference junction - To clean a fouled junction:

Inspect electrodes for scratches, cracks, salt crystal buildup, or membrane/junction deposits.

Rinse off any salt buildup with distilled water, and remove any membrane/junction deposits as directed in cleaning procedures below.

The reference chamber should be drained, flushed with fresh filling solution, and refilled.