Hi,

when I use the potassium ISE (ion-selective electrode) and the pH meter probes alone in the beaker the signal and the measurement is correct but if I immerse the pH meter probe in the same beaker as the ISE, the signal changes dramatically for both the pH meter and the ISE. what is the reason? I must use them both at the same time in the same solution and I don't know how to avoid it?

I have tried different pH probes and the same thing happens. I have used potassium and nitrate ISE and the same thing happens as well!

Thanks