I have recently started all-grain brewing (BIAB) and am interested in how water chemistry impacts my beer. I've been using RO water with maybe a Tbsp of gypsum for a 5.5 gal batch.
I live in Phoenix, so the water is pretty hard. The city water report seems a bit sketchy for brewing purposes because:
I thought about having my tap water tested by Ward Labs, but based on the variability above I'm not sure how useful that would be. That is, it would tell me what my tap water chemistry was on the day it was sampled, but what would it be weeks or months later? Braukaiser's recommendation of using an aquarium test kit to monitor KH and GH as a way to know whether it might be time to send off another sample to Ward makes sense, but that sounds like it would get kind of old.
I'm thinking the best approach may be to continue using RO water from my local water store and make the adjustments recommended in ajdelange's Primer. The cost is negligible and so is the hassle.
Now for a couple of questions:
I live in Phoenix, so the water is pretty hard. The city water report seems a bit sketchy for brewing purposes because:
- It's published only once a year
- Of the ion concentrations of interest to the brewer, only sodium is listed.
- For the measurements that are reported (alkalinity, total hardness, sodium, and pH) Low and High values are give with no indication of whether the values were measured in different locations, at differnt times, or what.
I thought about having my tap water tested by Ward Labs, but based on the variability above I'm not sure how useful that would be. That is, it would tell me what my tap water chemistry was on the day it was sampled, but what would it be weeks or months later? Braukaiser's recommendation of using an aquarium test kit to monitor KH and GH as a way to know whether it might be time to send off another sample to Ward makes sense, but that sounds like it would get kind of old.
I'm thinking the best approach may be to continue using RO water from my local water store and make the adjustments recommended in ajdelange's Primer. The cost is negligible and so is the hassle.
Now for a couple of questions:
- Is all RO water esentially the same, at least as far as brewing is concerned? Or do I need to think about sending a sample of my store-bough RO water off to Ward?
- I read somewhere that monitoring total disolved solids (TDS) is a way to make sure that RO water is good (i.e., that the membrane filter is doing its job). Is this correct?
- In addition to the CaCl2, gypsum and sauermalz, what salts/additives am I likely to need to add if I start with RO water? I brew mainly ales, but have been thinking about giving lagering a try.