Many brewers use reverse osmosis water and salts to build their breweing water. While that gives them the flexibility to come up with the ideal water for a particular beer, it also adds new variables that can be messed up.

I have been doing this for the last 25 batches (since we moved into our new house) and in the beginning I didn't know what to aim for. Sure, there are the waters of the classic brewing centers, but they are difficult to capture exactly with the use of the commonly used salts (Gypsum, table salt, epsom salt, calcium chloride, baking soda and chalk) since the addition of one ion requires you to also add another ion. So I was more faced with the decisions of what ions matter for the beer.

In another thread is was asked to post a few of my water recipes. when reading these recipes, keep in mind that reverse osmosis doesn't strip out all ions from the water. It only takes out about 90-95%. My RO water had a TSD (total dissolved solids, the meter came with the RO system) of about 33 and the tap water was about 450. Now the RO water is at about 65 TDS, which means that I should replace the membrane soon.

I use this water for my Alts: the sulphate and Mg levels are kept low though the also could be higher to bring out the hops. But I haven't played with that yet. I wanted the calcium to be above 50 ppm (Palmer indicates that this is good for the yeast) and the bicarbonates are chosen to get me a residual alkalinity of about 100 mg/l HCO3. For a dark amber beer, this gives me a mash pH of about 5.3 which is generally my target

30L (8 gal) reverse osmosis water +
0.4g NaCl
0.3g MgSO4
0.9g NaHCO3
2.0g CaCO3

(58mg/L Ca; 3mg/L Mg; 32mg/L Na; 10mg/L SO4; 21mg/L Cl; 150mg/L HCO3)



This I use for a light colored pale Ale. It mimics the water I had in NC:
The increased sulphates bring out the hops and a residual alkalinity of 20 gives me a pH of 5.3

30L (8 gal) RO water+
1.6 g CaSO4
1.2 g NaCl
0.6 g MgSO4
1.0 g CaCl2
0.4g NaHCO3
1.4g CaCO3

(44mg/L Ca; 5mg/L Mg; 24mg/L Na; 45mg/L SO4; 44mg/L Cl; 60mg/L HCO3)


When building water use a program and make sure all the ions stay within reasonable bounds. Palmer suggests these:

Ca: 50 -150
Mg: 10 - 30
HCO3: 0 -250
Na: 0 -150
Cl: 0 - 250
SO4: 50-150

Kai