First time water treatment...looking for advise

[Furious_D]

Brewing a cream ale tomorrow and looking at water adjustments for the first time. I tested my water and inputted the info into the Bru'n water spreadsheet. I understand the sparge water acid addition, but cannot quite grasp how much lactic acid to add to the mash. Recipe below and screen shots from the spreadsheet attached. Any help is appreciated.

8 lbs Pale Malt, Maris Otter (3.0 SRM)
1 lbs Corn, Flaked (1.3 SRM)
8.0 oz Biscuit Malt (23.0 SRM)
8.0 oz Cara-Pils/Dextrine (2.0 SRM)
1.00 oz Hallertauer Hersbrucker [4.00 %]
0.50 oz Saaz [3.75 %] - Boil 10.0 min
0.50 oz Saaz [3.75 %] - Boil 0.0 min
1.0 pkg Safale American (DCL/Fermentis #US-05)

Brew on!

 

[mabrungard]

You have to enter trial additions of acid at the bottom of the water adjustment sheet and either increase or decrease that addition until a proper pH is produced.

By the way, your water is a bit too mineralized for brewing use...even if you acidify it. Because of the magnesium and bicarb levels, I suggest you consider diluting it 1 to 1 with RO or distilled water. Then figure out how much acid you will need in the mash and sparge. Considering the bicarb content of the tap water, using lactic acid is almost certain to create a lactic 'twang' to the beer.

 

[ajdelange]

You tell me your bicarbonate but not your alkalinity so I have to guess that the alkalinity is something like 8.67 mEq/L (434 ppm as CaCO3). That is a LOT of alkalinity. This water isn't really suitable for brewing because of that fact alone. To use this water you are going to need about 90% of that per liter as acid just to get the water to mash pH. That's 116.5 mEq assuming that you mash with about 1.6 qts/lb and want target pH of 5.5. Then you will need another 18.5 mEq to get the grains to target pH for a total of about 135 mEq. To pH 5.5 88% lactic acid is about 11.5 N (each cc delivers about 11.5 mEq) so you'll need approximately 135/11.5 = 11.7 mL for the 4 gal of mash water and the mash. Water to be used for sparging has to be brought to 0 alkalinity relative to mash pH. For 5.5 mash pH and alkalinitry of 8.6 that means 29.25 mEq/gal. At 11.5 N the requirement for 88% lactic is 29.25/11.5 = 2.5 mL per gallon.

Again, that's a lot. Way too much in fact. To make this water suitable for brewing you would have to boost the calcium and then precipitate out calcium carbonate by heating or the addition of lime. You are probably better off going to RO.

 

[Furious_D]

thanks for the advise. I updated the spreadsheet using 50% RO. Does this look better?