Realized this weekend that not all RO water fits the profile in brunwater. i had been using distilled water until my RO system was installed. brunwater was working perfectly for my brewing salts and acid additions - allowing me to hit my desired PH. when i switched to RO water and used the RO profile in brunwater, my PH became more difficult to hit -requiring some mid mash adjustments. I realized that the default alkalinity and water profile loaded in brunwater may not match what my RO water profile really is (i have sent off a sample to confirm my hypotheses), and was therefore ending up more acidic than i wanted in my mash. This weekend I switched profile to distilled, used my RO water,and found i was right back on target for my mash PH again - requiring no mid mash adjustments.
An RO membrane probably works at its best when new. And of course it depends on the water coming into the system, on how well RO will clean things up. Still I’m surprised theres much of a difference. I thought RO was only supposed to be around 20ppm Ca and not much alkalinity.
My ro system came with a tds meter. The water going in is over 300 ppm and pH is high 8s. The filtered water is 10-15 ppm and pH is mid 5s. The 1 year prefilters are 10 months old and the 10 year ro membrane is 6 years old.
At the bottom of the water adjustment sheet you can modify the values of the built in RO profile to match your RO water, no?
My RO water came back from Wardlabs as:
pH 7.8, TDS 26, Ca <1, Mg <1, Na 6, SO4-S <1, Cl 7, Bicarbonate 3, Alkalinity 3
that’s correct- you can enter them…i just haven’t got them yet. im also thinking that something else may have happened with the ph. 16ppm of bicarb for RO profile vs 0 ppm distilled profile would only be about .03-.04 difference in the final PH
Yep! The RO profile in Bru’n Water represents the result when sodium-laden, high alkalinity water of my city’s water system is run through the system. Therefore, the ending sodium and bicarbonate content may be a little higher than another system might produce with another water. This result is not surprising.
I am surprised that 16 ppm bicarbonate that is represented by the stock RO profile altered your observed pH results that much, but I suppose its possible.
By all means, do replace the various ion concentrations from your testing results in the water table that is at the bottom of the Water Adjustment page. All of those ion concentrations in that big table that are in those blue colored cells are changeable. If you don’t like the amount of sodium or whatever ion in any of those profiles…change them based on your experience. That way you aren’t limited to those stock profiles. The profiles were left changeable so that your preferences could easily be implemented. Just remember, if you change an anion, you will have to adjust one of the cations in the same direction to get that adjusted profile to balance. Don’t create a new profile that doesn’t balance. The water table reports the anion and cation totals so that you can see when the profile is rebalanced.
Enjoy!
Martin- I’ve got some exploring to do. When I used distilled, if it called for 2ml of lactic to hit a mash ph of 5.3, then I was generally right In range. I will be interested to see my RO water lab results. Something is a little off now, and the amount of lactic acid actually required is about .5 ml less than what I’m calculating in the brunwater profile. I have to see if perhaps it was the different grain I used, or if its something with my RO water…experimentation to follow!