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Bert H · 05-24-2006, 05:35 AM

Nice correlation with CO2 degassing and time there

. You have verified the advice we're all giving about letting your water sit out for 24 hours to measure the degassed pH as accurate. The pH variation you see at 18+ hours, is a measure of the limit of the pH probe you're using, apparently +/- 0.1 unit.

I remember reading somewhere in the dark ages of my earlier college years, that pure water, which is basically what the RO water you're using is, is hard to pH because of the lack of ions (therefore electrical conductivity) in the water. I am surprised by the high pH of a pure sample of RO water with a kh of 4. We need some chemists to chime in here.

05-24-2006, 05:35 AM	#3 (permalink)
Bert H Moderator Join Date: Mar 2004 Location: Alachua, Fl Posts: 4,886 iTrader Ratings: 108 iTrader Positive Rating: 100% Plant Points: 183085	Nice correlation with CO2 degassing and time there . You have verified the advice we're all giving about letting your water sit out for 24 hours to measure the degassed pH as accurate. The pH variation you see at 18+ hours, is a measure of the limit of the pH probe you're using, apparently +/- 0.1 unit. I remember reading somewhere in the dark ages of my earlier college years, that pure water, which is basically what the RO water you're using is, is hard to pH because of the lack of ions (therefore electrical conductivity) in the water. I am surprised by the high pH of a pure sample of RO water with a kh of 4. We need some chemists to chime in here.