Join Date: Feb 2012
Location: Ontario, Canada
I think the result will vary, you have to understand RO coming out from your system is not the same as the RO from mine. The water source still plays some role. Sure, TDS will be similar (near 0) as anything size bigger than the "holes" on the membrane will be filtered out, but what about the difference in electronic state (or whatever it's called in English, the H+ and OH- and other ion thingy), there are things that don't get filtered out by your RO.
For example, my tap has PH7.8, my RO freshly out of the system is PH 6.5, but if I age it for a few days then it creeps back to 7.0 - 7.2, if I age it even longer (weeks) then it creeps back to 7.8 or just a tad lower. If your tap is more acidic, please do an experiment to compare and share. I understand PH is very unstable in RO due to low TDS, but my observation is based on repeated tries, and very consistent.
Just my guess/theory, not claiming to be correct but that's what I'll stick to until proven otherwise.