"Tasslehoff" wrote in message
u...
I think it's usually stored in Ph 4 solution and KCl(Potassium chloride)
sold in gardening/hydoponics as potash. DO NOT use K2SO4(Pottasium
sulphate) also labelled as potash depending on the brand.



I have a Hanna Instruments PH tester and my instructions are to store in PH
7 solution. You should check the manufactures specifications for your
particular unit .

Rick