Myron L D-6 - Manual (Page 39)

Leaving high pH (alkaline) solutions in contact with the pH sensor
for long periods of time is harmful and will cause damage. Rinse
such liquids from the pH/ORP sensor well and refill it with Myron L
pH Sensor Storage Solution to extend the useful life of the sensor.
If unavailable, you can use a saturated KCl solution, pH 4 buffer, or
a saturated solution of table salt and tap water, but this should be
replaced with storage solution as soon as possible.
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 pH/ORP sensor well and conductivity cell with
clean water immediately after taking the measurement. Any sample
element that reduces silver, such as cyanide, will attack the reference
electrode.
NOTE: The instrument’s pH/ORP sensor has no field replaceable parts.
Should the pH/ORP sensor require replacing, ref. pH/ORP Sensor
Replacement (D-6), pg. 33.
36