Most all beers ranging from 8-14 SRM will have mashes right in the realm of 5.3-5.6 PH with no water manipulation.
In very light styles of beer you will have to acidify the mash some to bring the PH down.
[color=#FF8000]Edit: Jtb got a post in before I got mine up. We have pretty soft water but for delicate styles like pilsner you will need to acidify the mash if you want to hit on all cylinders when making this style. If you were to mash in as/is you will end up with a higher than desired PH. For example if using the water straight out of the tap with nine pounds of pils malt you will end up with a room temp mash sample showing 5.8-5.9 which translates to a mash temp PH of 5.5-5.7
You would really like to see a mash PH of 5.2-5.3, not 5.5-5.7 for a pils or other similar style.
Its not a deal killer but your final beer will have a higher PH than desired also which is the difference between a crisp clean pils and a flabby/insipid tasting pils if semantics matter to you. [/color]
In very dark styles of beer you will need to add lime or other minerals to bring the mash PH up.
As is St Paul water is great for brewing although there are three aspects to be aware of which will require starting to learn basic brewing water manipulation. Two newer free applications let you do this with ease and without a PH meter compared to a few years ago before these technologies/ research existed.
The three concerns a St Paul water user will have is:
Most months of the year our water is higher in Chloride and lower in Sulfate. This will make many beers appear to taste malty to very malty. You can use the below apps to bring the sulfate up and find a balanced to bitter profile if your beer style requires it.
Our calcium amounts range from 17-25ppm and this should be boosted closer to 50ppm in the mash and kettle full for more efficient mashes/ boils and fermentation.
Our chlorination level is usually very high so it is wise to add 1/4 tablet of campden per 5 gallons of water used.
The two applications to make it all easier on your learning curve:
A. Bru n water (Read the instructions tab very good complete information on the whole subject of water manipulation.)
B. Braukaisers water app.
http://www.brewersfriend.com/mash-chemi ... alculator/
That’s the basics, If you wish to know more do some searches on the forum as I have spoken to St Paul water manipulation too many times to count and do not want to rehash old text.
St Paul publishes each months report the following month around the 15th. Many times they are
late to publish reports.
Current data available: June 2013
HCO3 is not shown on the monthly report just take the alkalinity value and times by 1.22
Sulfate/ SO4 is not shown on the monthly report just take the sulfur value shown and times by 3
Link to St Paul’s water monthly test page: