Hi,

I've recently setup my KH Director here, connected to my Profilux 4.

I seem to be seeing a difference of around .5 KH from my manual measurements with my Red Sea pro test kit....

I have taken the time to calibrate my pumps, and see exactly 100ml when manually dosing each pump.

My KH is at 8.4 according to my manual tests, but I am seeing anything from 7.9 to 8.1 on the KH Director.

I have validated that I am seeing no air bubbles.

What could be causing this difference?

Many thanks,
Paul.