pH Meters and Calibration

ALL pH meters need to be calibrated using buffer solutions. The brand doesn't matter—you could use Oakton solutions with a Hanna meter or vice versa.

So what buffers will you need? Everyone will need a pH 7 buffer. Some of the economical meters say they have "one point calibration". In this case, all you need is the 7 buffer. For meters that have 2- or 3-point calibration you will need a 7 along with either a 4 or 10 buffer. You may need both, depending on the type of solutions you are testing. You'll want a lower range buffer (4) for solutions that are more acidic or have a low-pH range and a higher range buffer (10) for more basic solutions.