pH electrodes are delicate measuring instruments that require proper care and
maintenance to produce accurate and reliable results as well as to ensure a long
If an electrode is not in use always keep it moist by placing the electrode's glass
bulb in the storage solution (3M KCl). Do not store the electrode in distilled or
deionized water as this will cause ions to leak out of the glass bulb and reference
electrolyte, which can cause a slow response and damage the electrode.
Electrodes may be shipped with either protective caps or in electrode soaking
bottles to prevent cracking or scratching and to keep the glass bulbs moist.
Gently remove the electrode from the storage bottle and rinse it with distilled
water before use. For long-term storage, always keep the electrode in the bottle
in enough storage solution to cover the bulb. Replenish the bottle as needed.