British Waters, Hardness, Alkalinity, TDS and Treatment.

[Eric]

Britain is comparatively small compared with the nation from where most current brewing software emanates. We have common latitudes only with its most northerly State, Alaska. For centuries weather systems have passed over Great Britain in just a few hours. Areas that were once dessert have become lush pastureland and while rainfall isn't uniformly distributed, all British supply water supplies begin existence as evaporated sea water acidified by carbon dioxide. Accordingly many problems experienced by North American homebrewers, for whom the primary choice can often be RO water, do not exist in Britain. All too typical chart of this summer's weather showing impending rainfall for brewing liquor supplies.

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Rain falling on impervious rocks, such as granite and slate, quickly run off forming streams or lakes. That falling on porous rocks of limestone or chalk is absorbed to dissolve soluble inclusions, and being acidic, react with carbonates to form solutes until stopped by an impervious layer below, and potentially form an aquafer.

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Surface water is generally soft, low in minerals and alkalinity, while borehole water will be hard and high in alkalinity, although there are exceptions. One such is in some higher Pennines, that consist mainly of limestone, but can have intervening layers of millstone grit. The former is porous and soluble and the latter impervious and insoluble. Acidic rainwater (typically pH 6 with TDS of 10) dissolves the limestone above and at the edges, when overhanging grit collapses under its own weight. This can be plainly seen by the profile of Ingleborough and other fells.



An example of this exception is at Timothy Taylor's of Keithley, below which is the River Aire, 20 miles from emerging at the bottom of Malham Cove saturated in limestone minerals. Here, I assume, rainwater running off a millstone grit shelf, then through the thinned out limestone beneath and potentially repeated until trapped above grit below the brewery and still quite soft, is forced up the brewery's borehole. How their water is treated is better left to them in their video. https://www.timothytaylor.co.uk/brewing-process

We frequent read that British brewers boiled their hard water to reduce that and alkalinity for mashing, but above is where soft water is boiled (possibly to reduce the effect from sheep) and then hardened. We are told Guinness at its peak was made with soft water, but that soft water was used in their boilers and harder canal water was used for brewing liquor, as recorded in The Noted Breweries of Great Britain and Ireland.

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All with hard supply water know any vessel used for boiling soon furs up and requires continuous acid treatment, which can be eliminated if the water is acid treated first. Hard water can be, by suitable treatment, advantageous to brewers of ales, but boiling to reduce alkalinity can be both difficult and expensive.

Hardness is the measurement of all calcium and magnesium in solution, but is usually expressed in terms of calcium carbonate per litre. If the individual units of calcium and magnesium per litre are known, then the equivalent value to express in terms of calcium carbonate is 2.5 times the calcium content plus 4.1 times the magnesium content.

To be continued.

[clarets7]

[Eric]

My supply water is hard, it comes from a well in magnesian limestone, bored in 1841, after the cholera outbreak in Sunderland a few years earlier. The town was a major shipbuilder and thriving port with insufficient clean water for its population. Fortunately, a solution lay less than 200 feet down, in the remnants of a shoreline of the ancient, inland, long since dried up, Zechstein Sea outlined below.


This strata is seen as an outcrop from South Shields to Nottingham, but continues underground to the east, on lower contours as the Zechstein shoreline moving as it evaporated. Its water has been used by many breweries, including at Tadcaster and Mansfield, renown for their beers.

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By its name it contains decent quantity of magnesium, and so does the water it supplies, but makes good beer and is quite easily treated. That borehole is the only source for my supply and while heavy rain dilutes the mineral content, analyses and graphs confirm it is possible to determine all major ion content with adequate accuracy from a single TDS reading. This was the output of my calculator for my last brew, it's rough and ready needing a bit of human interpretation, for example the salts are split and added to the grain bed and the boiler determined on the day, there already being a good level in the water.

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The correlation between TDS and ion levels are determined using the function determined using the chart function of Excel, as shown below.

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[Eric]

A sample of my water was tested using a Salifert KH kit producing a figure of 240 mg/l as CaCO3. 750 ml was then titrated using CRS, and the findings entered into Excel and using the Chart Wizard, displayed a trendline. It was thought that 1ml of CRS would eliminate all alkalinity, but it didn't quite and a further charge of acid was required.

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It can be seen that somewhere between pH 5 and pH 4, all alkalinity was eliminated, the particular point we will find later. All was not done in laboratory conditions and was subject to the accuracy of my measurements, which were my usual best imperfect estimate, the stability of my meter, which was pretty good, the accuracy of buffers used for calibration, plus any outside influences not countered. In truth, all those should be accurate enough from a brewing point of view. Of course we usually rely on the findings of a Salifert KH test kit, which is good enough for me, but as some know, not for all, depending upon an indicator's colour to decide the end of alkalinity, the equivalence point.

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The indicator used in the Salifert kit is likely a mix of Bromocresol Green and Methyl Red, which as the above shows might be at pH 4.6. That fits well with my graph, but for a moment, we might consider where the equivalence point might be for pure water that has none? Wouldn't that be at pH 7.0? So what about water with just 10 ppm alkalinity, highly probably not 2 less than pH 7 and likely while the Salifert indicator still shows blue. But then again, anyone with low alkalinity supply isn't likely to need to reduce alkalinity in most brewing circumstances.

Taking those figures for pH and CRS volume titrated from the chart at the top, the last 10 readings were transposed, and with volume of acid transposed into the quantity of alkalinity CRS would potentially neutralise. Zero alkalinity was set for the final reading of the titration. These were then entered into Excel, using the chart wizard to create a curve through the equivalence point, the point at which alkalinity is assumed to be terminated and the point where the trend of the curve will change, an inflexion point.

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[Eric]

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The above was snipped from a page from https://chem.libretexts.org/ to describe better than I can, the equivalence point on the titration curve. That is the point wanted, and at what pH that titration suggest it was.

When alkalinity in supply water is titrated using acid, in this case CRS, pH falls, but as the equivalence point is approached, the plotted curve steepens. Maximum steepness occurs at the equivalence point, when all remaining alkalinity is neutralised, and from then, the steepness of the curve lessens. This is known as the infection point in mathematics. Google again coming to my help.

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But to find that point, I first put the curve on its side by swapping the x and y axes, with pH on x axis, the equivalence point than at the least steep part of the curve.
Next the volume of acid titrated was replaced by a measure of the buffering offered to the acid. 1 ml of CRS is known to neutralise 183 mg of CaCO3, but as the titration done in 750ml of water, I would prefer to alter the figures to represent titration in 1 litre. This would allow the figures obtained to be more readily converted to mequ if desired. This required a one third increase to compensate. This meant the volume of acid needing to be increased by a third, such that 0.1ml would need to neutralise 24.4 g of CaCO3 and 0.01ml, 2.44mg of CaCO3. In retrospect it was a mistake to introduce this complexity at this stage, but as it is usual to measure units such as alkalinity in units per litre, I thought it best to convert my measurements into litres rather than to keep the volume as 750ml. If necessary, I'll go over again this later.

So we now enter the world of calculus, and if we differentiate the formula of that plot, we get a formula for its slope and then fine pH at the oint of least slope.

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The object here was not to show how this can be done, it's obvious to anyone doing a titration on hard water where, within a hair's breadth, is the end point for alkalinity, but for soft water that maybe isn't that easy as I might be confirming when I test some after this is posted.

[MarkA]

Very interesting post Eric, thank you.

[Eric]

It has to be said that not all soft water will have low alkalinity. There are some waters in UK, and more in US, where the calcium and magnesium levels are low, but have sodium present in alkaline (carbonate) form. Fortunately such water isn't commonly found in UK.

Soft water is something I've little experience of, and it gave me some surprises. The rate at which my pH meter responded in was one, while aware that sticking a pH meter probe in DI water is a waste of time if expecting to find a meaningful reading, It had not occurred to me that lower buffering of softer water would have its own problems.

Measurements so far in this thread were largely taken several years ago. Then, after using Salifert reagent from an old kit, it came home how inaccurate it can become if used over a long period, when water can evaporate to create a more concentrated acid.

Before measuring alkalinity of my own supply from a TDS reading, the Salifert KH kit's reagent life was short as almost a ml and more required per test. Now little reagent is needed to test the alkalinity after treatment in accordance to TDS findings and the amount supplied can last for yonks. So, when comparing the findings for this post of a Salifert test and a calculation from a TDS reading, the finding was a vast difference. The old kit's reagent had been around for goodness knows how long was used, and produced a low, and obviously incorrect measurement. Those with low alkalinity water doing Salifert alkalinity tests may find their kit will last ages, but be aware the reagent will strengthen over time and can lead to inaccurate readings. New kits should be purchased on a regular basis. As it was, I had an unopened bottle of reagent, so redid the test.

The TDS meter indicated 480ppm in my supply water on this occasion, which from my Excel spreadsheet suggested alkalinity to be 221.4ppm CaCO3.
A new bottle of Salifert reagent produced the following colours at the indicted remaining content of the syringe.
0.26 blue began to fade
0.245 grey/blue
0.235 grey with slightest blue tinge
0.23 grey
0.215 very light shade of pink
0.205 pink.
By interpolation from the supplied chart, the fully pink would be 221ppm as CaCO3.
An absolute fluke without doubt, I'd hoped it would be near to be credible, but this was what I actually found and is likely the only point on the curve this might occur.

Next a Salifert test on softer water from Derwent Reservoir with low alkalinity.
0.93 mostly pink until well swirled when it returned to blue
0.915 mostly pink until well swirled when it became grey.
0.905 pink
By interpolation the last reading implies alkalinity to be 21ppm alkalinity as CaCO3.

Then this softer, low alkaline water was titrated with CRS diluted such that a similar volume of titrant was used as for the first titration in this thread.
The readings taken that showing the curve each side of the equivalence point were then charted on Excel, again with pH on the x axis. The y axis was this time the volume of unused titrant, the units being irrelevant when the object is just to determine pH at the inflection/equivalence point. The corresponding equation of the trendline was produced by Excel.

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Then, finding the pH at the equivalence point, higher than in more alkaline water.

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Higher pH than in higher alkalinity water, but then alkalinity is such that the difference is small enough to not be relevant for most brewing purposes.

[Eric]

Thus far the emphasis has been on hardness and alkalinity, but without a grasp of what those might be, water treatment can turn into a jungle, a tangle of seemingly unconnected strands that make little sense, not helped by foreign opinions of how British brewers made their beers.

Home brewers with hard water can successfully boil their water to reduce alkalinity to an acceptable level, Graham Wheeler did, despite writing a water treatment calculator. But making 5 gallons a dozen or so times a year isn't remotely comparable to a commercial brewery's workload. As all living in a hard water area with an electric kettle know, removing limescale is a constant and undesirable task, unless the water is first treated before making pale beers.

My grandmother, born in 1886 lived in the same house from being married. She had a cast iron fireplace with side oven with a kettle always on the hob. That probably started life with a 5 pint capacity, but when I knew it, capacity was possibly 2 pints at best, the rest taken by solid limescale and a loose pot ball that supposedly limited the build up.

Alkalinity of brewing liquor has a significant influence on mash pH and also when sparging. There was a period when Residual Alkalinity was an in vogue determiner for water treatment, based on the 1953 findings by Paul Kolbach of why mash pH with soft water could produce equally high pH wort as with hard alkaline water. For myself, residual alkalinity is the level of alkalinity after water treatment. That said, I have no axe to grind with Kolbach's findings, just with some who put them to unjust use. Kolbach found wort pH at knockout from the mash tun was raised by alkalinity 3.5 times as much as an equivalent amount of calcium would reduce pH, and that magnesium had about half the influence of calcium. A British paper to the Institute of Brewers in 1939 found similar, but suggested the influence of magnesium happened during boiling.

The following are a record of some simple mini-mashes. It is easier for me to post pictures of my contemporaneous notes, than via the keyboard, so sorry to any who cannot read my manuscript.

Pale malt was mashed for 60 minutes at 66C in a temperature controlled oven. These I usually do in single sessions at 15 minute intervals, using 20g of malt with 50ml of brewing liquor in standard glass tumblers.
The first used DI water, not RO as recorded, with Maris Otter pale malt, which after 60 minutes measured pH 5.65.
Second was a mash with my own water with its alkalinity reduced to the point where the so-called Residual Alkalinity was zero. This level of alkalinity was achieved by mixing untreated supply water with some of the same water titrated to the equivalence point with hydrochloric acid, to achieve the desired alkalinity level by calculation, then confirmed by Salifert test. After 60 minutes, pH stabilised at 5.52, but did drop a unit before the next sample was tested.
Third was a mash with the same supply water as the second, with alkalinity unaltered, but with calcium added in the form of gypsum to make the so-called Residual Alkalinity to be zero. This was achieved by adding 3.5 times the equivalent of the reduction in alkalinity of the second test, a significant quantity that probably wouldn't easily dissolve in water, but seemed to do so without difficulty in wort. After 60 minutes, pH stabilised for a significant period at 5.52, but again later was seen to have changed a point, this time in increase.

Two further tests were then carried out with that same water, one without treatment and the other with alkalinity titrated to the equivalence point with hydrochloric acid. pH was 5.74 with alkalinity as supplied and 5.44 with zero alkalinity. Neither had salts added.

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The interesting point to note is my second and third tests were as Kolbach predicted (to my surprise at that time), by reducing alkalinity of my water and then increasing calcium by 3.5 time the alkalinity reduction to produce the same pH reading. But the first test was with DI water, which has by definition zero everything, but gave a different pH with the same malt in the same proportions. Food for thought?

I would suggest that some alkalinity was added to the DI water used in that first test and 3.5 times as much calcium added as well, the resultant pH would likely return to that with the untreated DI water.

The units in the calculations are equivalents, not ppm or mg/l.

[Eric]

Without question, water is the major ingredient in beer, and brewing liquor composition influences quality of the finished product. It requires adjustment to achieve the correct composition relevant to the beers being brewed and solids dissolved in brewing liquor can substantially effect many beer properties including flavour.

Hard water contains calcium and magnesium substantially in alkaline form when drawn from chalk or limestone and high in sulphate from sandstone sources. Hard waters have fuller flavour and are thought to be most palatable and beneficial to consume.

Soft water mineral content is often very little, frequently from sodium and potassium sulphates, chlorides, nitrates and bicarbonates. Soft water tends to taste slightly soapy.

Brackish water contains a high proportion of sodium and potassium chlorides, occurring near underground salt deposits or some coastal regions. It tastes salty, but isn't common in Britain.

Peaty water occurs in areas near moorland and heathland and is normally soft. It is coloured, tastes bitter and can be phenolic.

All can be treated to produce good quality beers.

Historically, breweries originated on sites with their own water supply, to produce beer with regional characteristics. Many modern breweries and British home brewers use their local supply water, and while that water is potable, it is likely less than perfect for brewing. Further it will likely be desired to produce a range of beer types, each potentially requiring a different liquor profile.

Total alkalinity, also referred to as carbonate hardness, represents the carbonate plus bicarbonate content. It is measured by titration against a standardized acid and its pH increasing property has been known to brewers for over 100 years as the major water treatment procedure for most efficient beer production.
Being measured by titration, alkalinity has traditionally been recorded as the amount of calcium carbonate that would neutralise the amount of acid used for that titration, regardless of the form or forms that present.

Ions in water and malt.
Both water and malt supply ions to beer. Malt supplies modest quantities of calcium, sodium, sulphate and chloride with some minor ions, with significant quantities of magnesium, potassium and phosphate. There are significant interactions between ions from all sources during brewing, calcium and magnesium in particular reacting significantly with malt components, especially with respect to influencing pH. Non-reactive ions can influence flavour.

Effect of ions on beer flavour.

Sodium can contribute a salty taste at concentrations between 150 and 200mg/l, but at less than 100mg/l can sweeten the palate when associated with chloride.

Potassium has a similar effect as sodium, but only when present at significantly higher levels. A 1040 wort will typically have 400mg/l from malt.

Magnesium can introduce a bitter and sour flavour to beer, but that can depend on calcium level. When calcium isn't present, magnesium will effectively deputise, so the less calcium present, magnesium becomes more assertive. Malt typically provides 70mg/l.

Calcium is effectively flavour neutral except for its moderating influence on the tastes from magnesium.

Hydrogen influences pH, which influences taste.
< pH 4.0, beers tend to taste crisp, with dryness that improves perception of bitterness.
> pH 4.0 < pH 4.4, increase mouth coating and helps toasted characteristics.
> pH 4.4 increases mouth coating effects with soapy and possibly caustic characteristics.
It should be recognised that the use of organic acids such as lactic, acetic or citric used for pH adjustment or alkalinity reduction can significantly effect flavour of finished beer.

Iron has a significant adverse influence on beer taste, even at levels less than 1mg/L. I believe the UK limit is 200ug/l, which shouldn't be noticed in most beers, while the highest recorded for mine in recent times was <10ug/l. It can be of concern to those off grid.

Chloride will provide fullness and sweetness, enhanced at levels between 200 and 400mg/l.

Sulphate imparts dryness that increases the perception of bitterness. Again, at levels between 200 and 400mg/l the influence is more pronounced. I would add from personal experience, high levels of sulphate with roasted grains can result in significant bitterness that could spoil an otherwise superb stout. Also that while a superb Pale Ale will be produced with a higher level of sulphate, without some balancing chloride, it will need extra time to fully mature.

Sulphate:Chloride balance/ratio has been long debated to become a controversial subject. What I have found is that two beers with the same ratio of sulphate to chloride, one with 50ppm calcium and the other with 150ppm calcium, are different.

[mikenotts]

A masterclass - thank you. I turned 70 this year and I'm thinking of returning to brewing after a many years long layoff (I have a brewzilla in the spare bedroom, unused since pre-lockdown). Even when I wasn't brewing (or drinking) I was (am) always fascinated by everything about brewing and I love your matter of fact this-is-how-it-is exposition about how to brew top class excellent beer (I remember your brief spat with an Aussi BIAB guy before Jim calmed it down, about competing efficiency rates as I recall - definitely escalating to a no prisoners moment I'd like to have seen play out).

I always wonder how the hobby plays out in old age (smaller brews? less brews? give it away?) but Anywhoo, I have your previous posts on water treatment saved as Word docs so I'll add this to the list.

All the best and keep on brewing.

[Eric]

My thanks to those who have responded and to all following this thread.

Perhaps now I should indicate my intent for what follows. Brewing is a fascinating subject of science and skill, potentially trivialised by constant debate of which spreadsheet makes better beer, rather than what makes beer better.

After identifying and describing the vast majority of hard and soft waters in Britain, I wish to describe how both may be treated working from first principles, and what that purposes that treatment serves. Like all journeys, it is more likely to end successfully when you know from where one starts, and an analysis of your supply will likely repay its cost many times over for those in areas with anything but very soft water supply.

Mike, get your skates on. Believe me, time in retirement very quickly passes and next month will see me into my 16th year. I have a 25 Klarstein which appears by observation of advertising to be an absolute basic model of your Brewzilla. A vast step forward from mashing in a grain bag.

[Eric]

Some important influences in the presence of calcium ions when brewing.

During wort production, calcium aids enzyme activity of malt and protects alpha amylase from the adverse influence of heat to give greater extraction.

Oxalate derived from malt will deposit with calcium, that would otherwise form haze and cause gushing. 70 to 80 mg/l calcium in the mash is advised to eliminate excess oxalate during beer storage.

While soluble proteins are essential for good heading properties, less soluble proteins can and will give rise to poor clarity. While wort boiling denatures these proteins, cations, and in particular calcium, aids their deposit. For a good level of protein break formation, a minimum level of 100 mg/l calcium is advised.

Yeast flocculation is improved by calcium by strengthening cell walls. Many yeast strains will benefit from a minimum level of 50 mg/l.

Both calcium and magnesium as well as phosphates influence the interactions of proteins, polyphenols and hop iso-alpha-acids. Such formations can lead to greater clarity during boiling and increased stability during and after maturation.

The influence of ions in brewing liquor on mash pH.

The control of pH throughout wort production, fermentation and conditioning is fundamental to the quality of beer production, but perhaps there is no more vital stage than the mash, for if this stage is defective, little might be done to rectify the potential pitfalls of this stage. pH can be measured by brewers, as we check temperature and the absence of dough balls, to confirm, or otherwise, the progress of a brew, but the range of allowable pH is quite wide and good beer can be made without a meter. Indeed, I don’t measure pH every brew, but it is difficult to describe what to target for a mash without reference to it.

Briefly, pH might be said to measure the acidity or alkalinity of aqueous solutions. The scale is logarithmic, like that used for sound levels. Midscale is 7 and said to be neutral. Lower values are acidic, higher values alkaline. By calculation pH is minus log base 10 of the concentration of hydrogen in moles per litre, BUT knowing what alters hydrogen concentration is enough.

A tenfold increase in hydrogen concentration reduces pH by 1.0
A tenfold reduction in hydrogen concentration increases pH by 1.0
Doubling hydrogen concentration reduces pH by 0.3
Halving hydrogen concentration increases pH by 0.3

All the definitive pH values given in this text are those taken at standard lab temperature, whatever that might be today. Whether it be 60F or 25C makes little difference for the home brewer, but measuring mash at mash temperature is both bad for the meter and the brewer wishing to compare with advised findings.

pH of wort and beer is strongly influenced by the disassociated ions present. Malt supplies vast quantities of free phosphate (>500mg/l), greater than any likely level of both calcium and magnesium, which when disassociated will combine with phosphates and in the process release hydrogen ions to lower pH. Alkalinity in whatever form it takes has the opposite effect, and in terms of equivalents, for any give quantity of alkalinity calcium will have less than a third of the opposite influence and magnesium a seventh.

There isn't a single optimal pH for every aspect of the mash, but we need to know effects different pH can have. My first all grain beer was Dave Line's Guinness, so my highly alkaline water didn't raise pH as high as it did when later brewing a pale, and I quickly learned what astringency does to beer, but then didn't know what it was. Barley has a husk and high pH extracts from that what isn't wanted.
The enzymes that convert our malts to sugars, alpha and beta amylase have optimum performances at different pH levels, alpha at higher than 5.3 and beta at lower. Note the influence of pH on saccharification times shown the following table. Using European malts might require different treatment to those from other countries with more protein and enzymes.

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[Eric]

Total Dissolved Solids was initially measured by heating a sample of filtered water to 180C until dry, the solid minerals weighed before being chemically determined. The major ions in such samples would be determined while dozens of minor ions would not. Modern methods enable determination of many minor ions, which in Britain will contain few, if any, of concern to the brewer. This is not necessarily so in many other countries. Some British Water Companies publish details on their websites of the major ions for brewers, although these should be treat with some caution as they will be averaged values and potentially not necessarily contemporaneous with each other. TDS meters can be bought for little, but such instruments measure electrical conductivity (uS/cm) then apply a conversion factor to produce a readout in mg/L, but that can
Pure water, very rare outside the laboratory by its ability to dissolve many minerals, does not conduct electricity. In general, the more dissolved minerals, the more conductive it becomes, but different minerals have different influences on conductivity. Nonetheless, I found it possible to adjust a basic TDS meter calibrated for sodium chloride solutions to provide an adequately accurate TDS readings for my water supply. It has a single source and mineral content varies with rainfall. Simplifying matters for myself, TDS for recalibration was determined as the summation of calcium, magnesium, sodium, sulphate, chloride and carbonate. The last chosen because calcium bicarbonate does not exist in solid form, and levels of other ions were sufficiently low to be ignored.

Hardness, or soap destroying properties of a water is often expressed in degrees, a measure of soap required to produce a lather of certain dimensions lasting for a specified duration. Brewers understand hardness as a product from the quantities of calcium and magnesium present, which exist in most waters. Other cations, like iron and zinc, contribute to hardness are at very low levels in British water supplies, and while sodium and potassium are vastly more prominent, their influence is trivial. With hardness depending upon more than one mineral, it is usual, and helpful, to have it expressed in a single unit, usually in terms of mg of Calcium Carbonate/ litre.
Calcium has an atomic weight of 40.078 and CO3 molecular weight is 60.008, a combined total of 100.086, or thereabout after rounding.
Thus, calcium in mg/l expressed in terms of calcium carbonate in mg/l will be Ca multiplied by 100.086/40.078, i.e. Ca X 2.4973
Magnesium's atomic weight is 24.305, so combined with CO3 at 60.008 becomes 84.313
but magnesium expressed as calcium carbonate will be Mg multiplied by 100.086/24.305, i.e. Mg X 4.117.
For practical purposes, I use (Ca X 2.5) + (Mg X 4.1) to determine hardness in terms of CaCO3.
What practical purposes? I hear. Not a lot unless hardness and only calcium are given, when magnesium might be then calculated.

However, not only hardness can be expressed in terms of ppm or mg/l of calcium carbonate, it is also used as a measure of alkalinity. Knowing the amount of alkalinity in brewing liquor is critical when brewing and it is vital when coming across measurements in terms of CaCO3 to know what measurement it is. When brewing we don't always need to know the composition of any alkalinity, just its quantity and what we should target for the ingredients we will be using, and how that may be best achieved for the type of beer we intend to brew.

[simple one]

Brilliant thread.

[Eric]

Brilliant thread.

Thank you.