Myron L 6P (includes Addendum 10-01) - Manual (Page 15)

Leaving high pH (alkaline) solutions in contact with the pH sensor for long
periods of time can damage it. Rinsing such liquids from the pH/ORP
sensor well and refilling well with Myron L Storage Solution, a saturated
KCl solution, pH 4 buffer, or a salty tap water, will extend the sensor’s
useful life.
Samples containing chlorine, sulfur, or ammonia can "poison" any pH
electrode. If it is necessary to measure the pH of any such sample,
thoroughly rinse the sensor well with clean water immediately after taking
the measurement. Any sample element which will reduce (add an
electron to) silver, such as cyanide, will attack the reference electrode.
Replacement sensors are available only from the Myron L Company or its
authorized distributors.
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