thanks TOny I checked it I'm running the bubble rate around 100 bubble per min the gagues that i have is weird i have the ml coming out around 30 ml per min.
So i 'm leave it at around 80-90 bubble per min hopfully the p.h will stay at 6.5 it was at 6.3 with a ml per min at 25. for some reason I can't figure this stupid thing out.. its easy but i can't get it

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So if i run the bubble rate around 60-70 and get a ph of 6.5 leave it and adjust the flow rate to about 30 ml per min then RIght ..