Quote Originally Posted by Amir
using PS233 I get a PH of 7.5-7.6 but Henna PHep4 shows a ph of 8.I had just did a two point calibration on the meter. Is there a reason for the discrpancy?Thanks
Amir

http://www.hannainst.com/products/te...-%20HI%2098128

I've used Hanna products in the past, and have an extremely low opinion of their quality.

If you have a clear buffer that you can calibrate with, test the buffer with both the Hanna & the phenol red.

One caution: phenol red is NOT stable with chlorine levels above 3 ppm. The phenol red from Taylor, used in the PS200 should be stabilized to 10 - 15 ppm chlorine, but above that will give various false readings.

Ben