Water chemistry is perhaps the most important component that will take a good beer to a great one. However, it’s very common for brewers to eschew treating their water aside from perhaps removing chlorine or chloramines. Lots of the material regarding water makes it seem really complicated or calls for building everything from scratch via Reverse Osmosis or Distilled water sources. By building a very basic understanding of your water you can use one of several excellent tools to do all the heavy lifting.

The next few sections will cover some common questions that come up regarding water treatment along with some water profile examples from various municipalities. After this article you should have a good enough understanding of the most basic adjustments needed for your water.

Is my water good enough to use without any treatment?

There are three sections of a water report you should focus on to determine if your water is good enough to be used without any treatment: disinfectants used, ppms of Calcium and alkalinity.

Unless you are on a personal well then it is very likely that your water has been treated with some kind of disinfectant. The two most common are chlorine and chloramine which can result in medicinal off flavours if they aren’t removed from water. Chlorine can be easily removed by boiling or letting it sit overnight. Chloramines on the other hand cannot be removed using these methods and will require adding a bit of campden to your water. A single table is enough to remove chloramines from about 80L.

Calcium is important for so many parts of brewing that you should always be sure to have enough in your water. If your water has at least 50ppms of Calcium then you’re good to go. If you’re under then you’ll want to add a bit of calcium from either Gypsum or Calcium Chloride.

The final component you really need to worry about is alkalinity, which is waters ability to resist changes in pH. When we mash in our grains they release phosphates which can bring the pH of water down, but if your alkalinity is very high then you are at risk of having a high mash pH. High pH can result in decreased mash efficiency and possible tannin extraction during the sparge. Water can be treated with acids to help reduce your waters alkalinity or darker malts can be used. When brewing pale beers your only real option is to acidify.

Couldn’t I just build up the perfect water profile from scratch?

Yes you can, though it costs more and requires more organization to ensure that enough water is ready for the brew day. If you’re a bit of an environmentalist there is also the issue with RO systems producing lots of effluent that can’t really be used for anything else. Unless your tap water is completely unsuitable for brewing (smells bad, tastes bad, etc.) you can probably get away with using your water and cutting it with RO/Distilled.

Water Report Examples

The following will be an analysis of 4 water reports and what the minimum treatments would need to be made. Specialized water profiles will not be considered since that goes beyond the scope of this article. Focus will be spent on bringing calcium ions and alkalinity within acceptable operating parameters.

Toronto, Ontario, Canada

Ca

34.5 ppm

Mg

8.78 ppm

Na

13.7 ppm

Cl

25.2 ppm

SO4

26.5 ppm

Hardness

122.0 ppm (as CaCO3)

pH

7.9

Alkalinity

89.2 ppm (as CaCO3)

Anything brewed with this water is a bit low on Calcium so an addition of Gypsum or Calcium Chloride is most likely needed. If only one salt is going to be used, choose one that will benefit the style that will be brewed. For a hoppy beer Gypsum is the best choice since it will help accentuate bitterness.

The water is quite alkaline and will need some acids help bring mash pH down.

With very minor adjustments this water is nearly perfect for brewing any style of beer!

Guelph, Ontario, Canada

Ca

98.7 ppm

Mg

29.1 ppm

Na

25.5 ppm

Cl

44.9 ppm

SO4

83.3 ppm

Hardness

366.0 ppm (as CaCO3)

pH

7.9

Alkalinity

265.0 ppm (as CaCO3)

This water is fairly good since it contains more than enough Calcium to ensure a good mash and ferment. The only concern is the alkalinity which is going to wreak havoc on mash pH. Acidification of the mash water will absolutely be necessary and one should be careful if using Lactic acid since using too much can add undesired flavours.

This water will be good for most English styles, hop forward beers and darker beers. If brewing a pilsner or lighter coloured beers then cutting with distilled water may be necessary.

Stratford, Ontario, Canada

Ca

173.0 ppm

Mg

40.7 ppm

Na

19.4 ppm

Cl

8.2 ppm

SO4

423.0 ppm

Hardness

600.0 ppm (as CaCO3)

pH

7.82

Alkalinity

212.0 ppm (as CaCO3)

This is some tricky water to work with! It will be perfect for brewing extremely hop forward beers such as Burton-style IPAs. Even though the alkalinity is somewhat high, the hardness of the water is helping counter that. Acidification will be needed but it is very minimal.

Unless brewing exclusively bitter and hoppy beers this water will need to be cut with distilled/RO.

Gravenhurst, Ontario, Canada

Ca

15.4 ppm

Mg

1.06 ppm

Na

15.6 ppm

Cl

12.8 ppm

SO4

5.1 ppm

Hardness

42.6 ppm (as CaCO3)

pH

7.84

Alkalinity

53.7 ppm (as CaCO3)

Some calcium salts will be required to correct the very low levels existing in the water. The alkalinity is fairly low as well and you could chance not acidifying the mash water. To be safe some acid should be used to bring the mash pH into a more acceptable range.

This water is an excellent starting point for almost any style of beer; especially a pilsner!

Now get out there and play with your water!

Find a copy of your water report and put the values into some water software. Most municipality websites provide the information for free. Though if you are unable to find a report there’s tons on Brewers Friend, or if you’re in Ontario you can find some on Brewing Water Reports.