What is pH storage solution?

What is pH storage solution? The solution used to prevent the probe from drying out between uses.

I ask as there appears a white crust where the storage solution dried on the probe outside the storage cap.

Is the white crust a salt or chemical?

What do others use for pH probe storage? (Read best value).

Thanks.

I use storage solution and I get those crystals, too. I just rinse them off and move forward.

The pH probe storage solution is primarily potassium chloride.

My storage solution also states that it’s KCl.  And my probe explicitly called out that a white salt crust may form.  I assume that was to reduce support calls.  [emoji846]

I get the white crystals also.  I believe they’re a sign of evaporation of the storage solution itself.  So I made a habit of checking and refilling the storage solution often.

Potassium chloride is neither an acid nor a base.  So the pH of an aqueous solution of potassium chloride (KCl) is 7.  and to reinforce the previous comments, the crystals are solid potassium chloride which  come from the evaporation of the storage solution.