hmm interesting replies, thanks. My tap water is 140ppm and 7.8ph. seems like the ph hits around low sixes when I get it to 1000 ppm and them proceeds to drop as I go heavier. Ive been trying to keep things around 6.1 I guess. Im also considering switching to the hard water micro cause it seems that i might have a calmag issue??? tiny toon when you say you have a swing from 5.2 to 5.9 which direction is it going, up or down? thanks again.