Adjusting pH with BIAB and Bru'n

[pretzelb]

I must be missing something really basic but I can't figure out how to try and adjust my mash pH with Bru'n Water. Attached is the water profile sheet. My tap water isn't terrible but for a BIAB I estimate a 9.5g full mash using the Priceless tool. My adjustment summary shows the estimated mash pH of 5.9. I can't see a way to lower this even if I change the dilution percentage with distilled water. What am I missing?

 

[dpeters]

Looks like you need to add some Gypsum and Lactic acid to get to what your looking for. I would just get the calcium close to your profile with the gypsum and don't worry about hitting the 300 on the sulfate (I have never gone that high with the sulfate). So you just go to the water additions section below your finish water profile and add to the light blue field titled Addition gram/gal then check you PH output then you can go back and put in the light blue field for lactic acid and add some and then recheck PH output until you get the PH you want. I use Bru'n water and it gets me fairly close on PH and if its a little high or low I just adjust the next time I brew that beer rather than try and chase the PH.

 

[brew_darrymore]

As Dpeters suggested, add gypsum to bring your calcium and sulfate up; gypsum will also bring your pH down. You will need to top it up on top of the gypsum with some acid malt or lactic acid to bring your pH down to your desired range.

 

[ajdelange]

You don't say anything about the grains but the following synthesis will get your water to ion concentrations within a fraction of a percent of the target concentrations at pH 5.4 except for bicarbonate and we don't care about bicarbonate:

Salt/Acid/Base mg/L Synth mg/L Src
CaCl2.2H2O 63.76 136.36
NaCl 5.38 11.51
MgCl2.6H2O 6.54 13.98
CaSO4.2H20 392.05 838.45
MgSO4.7H20 155.64 332.86
H2O (DI) Liters 0.00 1.14
CaCO3 0.00 0.00
NaHCO3 8.44 18.04
CO2 0.00 0.00
HCl 0.00 0.00
Ca(OH)2 21.67 46.33
Na2CO3.H2O 0.00 0.00
Sodium Lactate 0.00 0.00
Potassium Lactate 0.00 0.00
Lactic 132.32 282.99
Sulfuric 0.00 0.0000

Obviously because your desired sodium is less than the target sodium you need to add DI water to your tap water in the amount of 1.22 liters RO/DO per liter of tap. If you do that first then add the amounts of salts and lactic acid listed in the Synth column to each liter of the blend. Or you can add the salts listed in the Src column to each liter of the source water and then add the blending water. The lactic acid requirement is, 3.0634 meq/L of source water or 0.221 ml 88% acid per gallon of the blend.

You will probably need additional acid to get your grist to mash pH. Assuming a typical grist with DI mash pH of 5.6 and buffering of about 40 mEq/kg•pH you'd need about 1.2 mEq/L lactic acid in addition to the 3.06 for the water getting you up to 0.3 ml 88% acid per gallon of the blend.

 

[pretzelb]

Looks like you need to add some Gypsum and Lactic acid to get to what your looking for. I would just get the calcium close to your profile with the gypsum and don't worry about hitting the 300 on the sulfate (I have never gone that high with the sulfate). So you just go to the water additions section below your finish water profile and add to the light blue field titled Addition gram/gal then check you PH output then you can go back and put in the light blue field for lactic acid and add some and then recheck PH output until you get the PH you want. I use Bru'n water and it gets me fairly close on PH and if its a little high or low I just adjust the next time I brew that beer rather than try and chase the PH.

I found the problem. On tab #4 (row 24 for me) you can choose for adjusted water or existing water. For some reason I picked existing. That prevents the changes from working. If I pick adjusted then I can see the effect of the changes. Stupid user error.