PH Drop with new RO system

[dpeters]

Ok, so I just installed a new RO system and before I was getting RO water from the store. I brewed a beer on Friday with my RO water and my PH was .5 lower than Bru'n Water calculated so this puzzled me enough to brew another beer today and see if the same thing would happen and sure enough it did. I did calibrate my PH meter (Milwaukee 102). Before this my PH has always been really close to what was calculated. Any Ideas or has anyone had this happen?

 

[day_trippr]

Makes me wonder about the TDS of your store bought RO.
In any case, does your Bru'n Water sheet reflect your RO output?

Cheers!

 

[dpeters]

Makes me wonder about the TDS of your store bought RO.
In any case, does your Bru'n Water sheet reflect your RO output?

Cheers!

I use the default RO Water in Bru'n Water and it has always come out really close when using the store RO water. With the new RO system at home my PH is 6.5 and a TDS between 5 and 8 Bru'n Water calculated that my PH should have been 5.6 and I got 5.1 I am not sure what the store TDS is as I have never checked it.

 

[day_trippr]

Woof. That's an epic miss.
Even if the "RO" water you used to buy was actually remineralized it wouldn't explain that big a miss using actual RO water.
Have to believe something's off somehow...

Cheers!