Imperial Stout Water Adjustment

[jjp36]

I'm going to be brewing an imperial stout in the next week or two, and recently stocked up on brewing salts in order to adjust my water from distilled. The problem is i have no idea what I'm doing. So I'm looking for help.

The beer is going to be big, OG around 1.100, with an SRM of 53 (1 lb crystal 90, 1lb chocolate, .5 lb roasted barley, .5 lbs debittered black). There will be 8 gallons of water for the mash and 3 gallons for sparge, which should net me a total of about 7.5 gallons pre-boil.

I have brewwater. Should i just be using something like Mosher's ideal stout profile and trying to match that? I'm just curious because i tried that and there is no mention of alkalinity, which i thought was important for a stout.

Any directions anyone could give me would be greatly appreciated.

 

[Netflyer]

I'm trying to figure out how much is too much salt(s) to my water in another thread so I'm no expert here but I can tell you the profile you might want to match is:

Calcium: 115.0 ppm
Sulfate: 55.0 ppmMagnesium: 4.0 ppm
Chloride: 19.0 ppmSodium: 12.0 ppmBicarbonate: 200.0 ppmPH: 8.0

For Dublin... if it is a dry stout... and Bicarbonate HCO3 is the total alk... and with a ta of 200 I'd say it is an outstanding characteristic of dry stout's character

Here I'll run distilled for you in beersmith and see how to get you close... again, I'm not sure what is too much to add. If you add too much your beer could suffer just by the nature of the salt. It could produce off flavors and I'm just not sure of the threshold... I messed with it in beersmith for ya and put in 11 gallons of water to be treated.

To get to Dublin like water you would have to add:

4 g of Gypsom CaSO4, 4 g of table salt NaCl, 3 g of Epsom Salt MgSo4, 1 g Calcium Chloride CaCl, 8g of NaHCO3 Sodium bicarbonate / baking soda, and 1.7g of Chalk CaCO3.

That gets you less then 10 ppm away from a dublin target from distilled water. Btw for me 1 tsp of Gypsom weighs about 3g but I use a scale when making these additions. Again, I don't know and hopefully someone else who does know will comment on whether it is ok to add this many salts. Or perhaps there is a better way to get to Ireland from distilled

Edit: My water question was answered by TH and he has this awesome spreadsheet:
EZ Water Adjustment spreadsheet

Use it to get your RA in line... Also, if you look at the sticky in brew science Bobby_M has an awesome video(s) on how to use that spreadsheet and adjust your water...