How do I test if my ph meter is working right?

[xX1cEpikKXx]

Its not the same tyke, but thx

 

[xX1cEpikKXx]

the powder that you add to the distilled water to make the ph 4.0 or 7.0 etc...has enough salts to make it not distilled water anymore once mixed.

Thank you

 

[nonamedman420]

Thank you

anytime

 

[Dr. John Hopkins]

Do NOT use Distilled water to store PH Pen!