Erroneous pH Readings

[leontet]

Well, I deleted the original post because the story was too long. To make it short, I had problems with the read pH values after re-calibration. I was puzzled by the fact that my GHL computer was working fine with another probe, but also the GHL probe was working fine on another computer. The bottom line is: ALWAYS USE FRESHLY PREPARED pH REFFERENCE BUFFER SOLUTIONS when performing probe calibration!!! End of story...