Originally Posted by Yooper
you're correct. Sparging with RO water should not raise the pH above 6.
What is the source of your RO water? I wonder if you can check with a TDS meter and make sure the RO water's membrane/process is working.
I have a small 5 stage portable filter from purewaterclub.com.
The water is run through a series of carbon filters, RO filter, and DI filter. I don't have a TDS meter but I see where you're going.