When my water comes out of my lab RO/DI the pH is usually pretty close to 7 (6.8-6.9) but within 5 to 10 mins the pH drops to 6 simply due to CO2 dissolving into the water. There's no need to worry about it though. If your wanting to keeptue top water close in pH, add a tiny bit of Kalk to buffer it.

Guys, what's Rule #1? Don't worry about pH! :lol:

Ok ok, I do see the point to this thread though. I should check my water and see what pH we get in Metro Vancouver. Interesting....