Water profile for a porter

[Shag]

I'm looking to start my brewing back up again after a year hiatus, but have forgotten all the water chemistry stuff I learned last spring. I'm looking to brew a porter this weekend, with an estimated SRM of 30. I'll be starting with RO water.

Suggestions on a good porter water profile?

Thanks!

 

[mabrungard]

Bru'n Water has everthing you need. Download it at the link in my signature line.

 

[Shag]

Bru'n Water has everthing you need. Download it at the link in my signature line.

Thanks - looking at that now. It's been suggested to me to use the London profile for a porter, but I noticed that your London profile is considerably different than the London profile in BeerSmith. It's mentioned in the instructions that other sources may be incorrect - should I assume that the Bru'n Water profile is better than the BeerSmith profile?

Playing around a bit, here's what I'm at now:

Finished Water Profile
Ca: 81.1
Mg: 5.2
Na: 72.3
SO4: 94.3
Cl: 89.3
HCO3: 191.9
Cations: 7.6
Anions: 7.6
Hardness: 224
Alkalinity: 159
RA: 98
SO4:CL: 1.1

How does that look for a porter? Is the RA too low? Predicted SRM is 30...

 

[mabrungard]

I'm a Promash user and the trial period on Beersmith is over for me, so I can't see what they have in there. Its possible they have a faulty profile since there are bad profiles everywhere on the web and even in print. I would not necessarily assume their profile is bad though. You can plug it into the Water Report Input and see if it balances. If it balances, then at least you can actually recreate it.

Another choice for a water profile is one of the Brown profiles that are canned in Bru'n Water. They end up in the 80 to 90 RA range and might be a good choice.

One thing to understand about Bru'n Water is that RA is only a rough guide. That program evaluates your actual mash to assess if the alkalinity of your brewing water is appropriate to produce a decent mash pH. Even though you start out with one of those canned water profiles, you have the tool that allows you to fine tune the alkalinity to bring the mash pH where you want it. For a Porter, I suggest that aiming for the 5.4 to 5.5 range (room temperature measurement).