Beer Forum

So I brewed a beer today with store bought water (the glacier machine), added salts to get a profile similar to Tasty's( Ca - 111, Mg - 18, Na - 20, S04 - 338, Cl -32), and acidified the water to 5.7. I mashed only maris otter malt. My room temperature pH sample after 15 minutes measured 5.1. Why so low?

Do you have the mineral report of the store water? Tough to hit a target by adding salts if you don't know what you're starting with. Not familiar with that brand, but the majority of those fill your own store fountains I've seen aren't R.O.

The glacier water is nationwide so I'd be curious if the water is different in different regions.

I was surprised to see at Walmart a RO water dispenser. I think I'm going to get a gallon and then send a sample to Ward Labs just to make sure it is legit. It will be a lot cheaper than buying 10-12 gallon bottles of RO every time I brew lagers. For my Ales, my tap (town provided community well ) water is sufficient with minor salt additions.

Have you checked your tap water?

edit: From the Glacier site, it looks like they run it through the RO process, among other things. http://glacierwater.com/ask-glacier/faqs/

From what I've heard, the machines filter your own municipal tap water, so they will vary by location. However, the machine lists several steps in their process, one of them being RO. I tested the pH of the store bought water and it came in at 6.2 (low right?). Short of human/mechanical error, and having the water tested, would brewing with acidic water and those Ca and Mg levels likely result in the mash dropping that low with only base malts. I've heard before that mashing base malt and distilled water will give you a pH around 5.6.

EDIT: After fooling around in brun water, it seems like the outcome I got is very likely given the inputs. On a side note, which water software do you guys like better, brun water or EZ water. Which one matches up better with your results?

Never trust store "RO" machines. I nearly killed a breeding pair of very expensive tropical fish changing water with that crap...

The Glacier machines are RO units. As with any RO water, you should have a TDS meter reading on that water to confirm that its relatively pure. But that is probably not the problem.

As hoodie found out by messing with Bru'n Water, the RO water does not have enough alkalinity (bicarbonate) to buffer all that calcium and magnesium hardness. This is why the Pale Ale profile in Bru'n Water does have some bicarbonate in it. Its especially needed when you start adding some crystal or roast malts to the mash.

Don't worry, that batch will still be beer. It will just be a little thinner and tarter than you might have hoped for.

Thanks Martin. Love your software. With this batch I tried to add all the salts at once, when I should have focused more on getting the mash pH right, and added the flavor ions later. Eventually, I will listen to the advice given by so many brewers. Eventually.