ok SO I FELL LIKE A RETARD AND CANT FIGURE THIS OUT..I JUST BOUGHT HE HANNA PEN AND AM TRYING TO CALIBRATE IT..IT HAS TWO SETTINGS 7.01 AND 6.0?...I JUST CAL WITH TAP WATER. I DONT KNOW IF I CALIBRATED IT RIGHT HOW WILL I KNOW? I DONT HAVE THE SOLUTION SO MAYBE THIS IS WHY..ALSO IM A NEWB FIRST...