I was looking for a hardness tester and across a Hanna Instruments HI98202
and looking at the manual and it says it tests hardness by
the pNa tester utilizes a sodium ion-selective
electrode to determine the activity of free sodium
Since it determines the activity of free sodium in a solution does using potassium still make the tester give the same reading as using salt ?
Last edited by jasper7821; 10-08-2012 at 12:51 PM.