Water Treatment Calculator Page

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Dont Panic! - There is a lot of text on this page because we want to explain things clearly and make it easy to understand - not because we want to try and show that we are clever or that this is hard!

This water treatment calculator is designed to allow you to adjust your water so that it is suitable for the style of beer you wish to brew. There are several water calculators available on the internet however they tend to be somewhat cryptic for non-chemists (i.e. the majority of us!). We have tried hard to keep this as simple as possible to enable as many people as possible to use it. If you prefer the cryptic chemistry style calculators then this is not for you.
The first thing most of us need to do to our water is remove the Chlorine and/or Chloramines which are used by the water companies to sterilise the water in our pipes. This step is not usually specified on other water treatment calculators however, if these are not removed, they can lead to a medicinal taste in the finished beer that is unpleasant. Chlorine could be removed by boiling the water however this will not work with Chloramine. Fortunately, simply adding half a crushed campden tablet (campden tablets are compressed sodium metabisulfite powder) to 25 litres of tap water before brewing will convert the Chlorine and/or Chloramine into other compounds which we cannot taste. If you are new to water treatment, you could simply continue to brew at this point and you should notice a marked improvement in the taste of your beer. If you would like to produce even better beer, keep reading...
Alkalinity and Hardness - Alkalinity is caused by carbonate and bicarbonate and has a negative effect on beer as it tends to keep the mash pH higher than we want. Hardness is formed by Calcium ions and Magnesium ions but Calcium is generally beneficial to beer as it lowers the mash pH and promotes clarity by increasing break formation and yeast flocculation. In order to acheive a good mash, we generally want to get the mash pH to around 5.2. In areas where the ground water has naturally filtered through chalk (Calcium Carbonate), the water can be quite hard because it has picked up the Calcium and also quite alkaline because it has picked up the Carbonate; in this case we are likely to want to reduce the alkalinity. Temporary Hardness can be removed by boiling the water which precipitates out the Carbonates (causing kettles to fur up) and leaves the Calcium (as permanent hardness) however there is a simpler way to adjust the alkalinity. Carbonate Reducing Solution (CRS) is an acid which is available from home brew shops and is used in small amounts to reduce the alkalinity. The calculator below will tell you how much CRS you need to add to your brewing water. In areas where the water has been collected from surface runoff (e.g. moorland etc), the water may be very soft and have a low alkalinity. Here we are likely to need to add some Calcium and in fact, it may be necessary to add some Carbonate to increase the alkalinity and stop the pH falling too low during the mash.
Different styles of beer benefit from different amounts of trace minerals in the brewing water. Traditionally different areas of the country were known for brewing certain beer styles which were suited to their water supply. Modern breweries tend to treat their water so that they can produce any style they wish. By adding small quantities of inorganic mineral salts, we can treat our water in order to make sure it is best suited to the style of beer we wish to brew.
Before we can determine the quantities of salts to add, we first need to know some information about our tap water which we use for brewing. This information is made freely available by local water supply companies and some of them have the information online allowing us to search using our postcode. Unfortunately not all companies are so helpful however they are happy to provide the information if requested. You may need to telephone or write to your water company to get the information. Here are a couple of links that you might find useful: www.water.org.uk and www.water-guide.org.uk.
Once you have your water report information, check to see if you have figures for the following parameters (Calcium Ca - Magnesium Mg - Sodium Na - Sulphate SO4 - Chloride Cl - Carbonate CO3). These are usually expressed in ppm (parts per million) or in mg/l (milligrams per litre), either is fine since they equate to the same amount. If you do not have any of this information then you may have only a basic water report - you will need to ask for a more detailed water report - often you can speak to someone and ask for exactly these parameters.
Often, they do not specify a value for Carbonate however they may specify a value for Alkalinity or Hardness "as Calcium Carbonate (CaCO3)" although they may specify it as Bicarbonate (HCO3). If they simply do not state a value for Carbonate (CO3) or Alkalinity or Hardness, you can measure it yourself using a simple procedure that takes about 5 minutes. THBF may be able to provide information about where to buy a kit or perhaps even sell you a kit to measure the Alkalinity of your water.
Now you have the figures, enter them in the boxes below:
Calcium (Ca): mg/l or ppm Enter value for Calcium from water report, e.g. 13.8 mg/l
Magnesium (Mg): mg/l or ppm Enter value for Magnesium from water report, e.g. 3.38 mg/l
Sodium (Na): mg/l or ppm Enter value for Sodium from water report, e.g. 10.5 mg/l
Sulphate (SO4): mg/l or ppm Enter value for Sulphate from water report, e.g. 30 mg/l
Chloride (Cl): mg/l or ppm Enter value for Chloride from water report, e.g. 12.5 mg/l
If your water report has a value for Carbonate (CO3), then enter that in the box below. If it does not specify CO3 then leave the box blank.
Carbonate (CO3): mg/l or ppm Enter value for Carbonate from water report, e.g. 13.2 mg/l
If you have not entered a value for Carbonate (CO3), but your water report specifies a value for Alkalinity "as HCO3", then enter that in the box below. If it does not specifiy a value for Alkalinity "as HCO3", then leave the box blank.
Alkalinity as HCO3: mg/l or ppm Enter value for Alkalinity from water report, e.g. 14.5 mg/l
If you have not entered a value for (CO3) or a value for Alkalinity "as HCO3", then either enter the value from your water report for Alkalinity "as CaCO3" or enter the value you have measured for Alkalinity "as CaCO3" using the sample kit.
Alkalinity as CaCO3: mg/l or ppm Enter value for Alkalinity from water report or sample kit, e.g. 11.9 mg/l
Next, we need to know what volume of water in total you will be using and what volume of water you will add to the mash:
Total volume of water: litres Enter total volume of water, e.g. 25 litres
Volume of water in mash: litres Enter volume of water in the mash, e.g. 10 litres
Now we know the composition of your water and what brew volume you will have, we need to know what sort of beer you wish to brew so that we can determine how best to treat your water. Please select the beer style below that most closely matches what you wish to brew.
General beer style: Select the beer style you intend brewing, e.g. Stout
Now we should have all the info we need to calculate what mineral salt additions you require. Please click the calculate button and then read the results below.
CRS: 0 millilitres Carbonate Reducing Solution - add this to the total water volume!
Gypsum added to mash: 0 grams Gypsum (Calcium Sulfate Dihydrate) (Ca SO4 2H2O)
Chalk added to mash: 0 grams Chalk (Calcium Carbonate) (Ca CO3)
Gypsum added to boiler: 0 grams Gypsum (Calcium Sulfate Dihydrate) (Ca SO4 2H2O)
Table Salt added to boiler: 0 grams Table Salt (Na Cl)
Epsom Salts added to boiler: 0 grams Epsom Salts (Magnesium Sulphate Heptahydrate) (Mg SO4 7H2O)
Calcium Chloride added to boiler: 0 grams Calcium Chloride (Dihydrate) (Ca Cl2 2H2O)
Ok, so you now know what additions you require. How do you go about adding them? Here's a guide:
1) If the calculator says that you need to use Carbonate Reducing Solution, measure it using a syringe and treat the full volume of water in one go.
2) Carefully weigh out the additions for the mash and mix them into the dry grain before mashing.
3) Carefully weigh out the boiler additions and add them to the boiler once you have completed sparging.
Salts attract and absorb water. The calculations above assume a specific level of hydration - if your salts are stored poorly, the will absorb water and change their weight consequently the figures above may well be inaccurate. When you buy your salts, make sure you store them in an airtight container in a dry place and only open then in a dry area for the shortest possible time while you weigh out the quantities you need.