Bluelab PH Pen Calibration

[@joshkroneberger479]

Is it okay for it to calibrate at 6.8 instead of 7?

[@wegrow4859]

6.9 is acceptable but 6.8 is a little out of range. We recommend cleaning the probe with a soft bristle tooth brush with Blue Lab's ph cleaning solution under clean running water. After, store it in Blue Lab's KCL storage solution for at least a couple of hours. It's extremely important to always keep the probe hydrated in KCL solution or 4.0 calibration solution. NEVER in reverse osmosis water. If is it still reading 6.8 after cleaning, storing, and calibrating then check the manufacturer serial #. The pens have a 1 year warranty from date of purchase. It should start with "BP1" then a series of four numbers. The first two represent the year and the next two the month. Ex: 1201= 2012 of January. Hope that helps!