Can someone help me interpret my water profile?

[Gordolordo]

I had my water tested recently and only have a very baseline understanding of water chemistry and what acceptable levels are for different minerals.

I *think* my water is pretty good other than being relatively high in bicarbonates and low in calcium. Am I reading it wrong?

pH 7.7
Total Dissolved Solids (TDS) Est, ppm 228
Electrical Conductivity, mmho/cm 0.38
Cations / Anions, me/L. 4.4 / 4.3

ppm
Sodium, Na. 68
Potassium, K. < 1
Calcium, Ca 27
Magnesium, Mg. < 1
Total Hardness, CaCO3 72
Nitrate, NO3-N. < .01
Sulfate, SO4-S 1
Chloride, Cl 9
Carbonate, CO3 < 1
Bicarbonate, HCO3 242
Total Alkalinity, CaCO3 199
Total Phosphorus, P 0.75
Total Iron, Fe. < .01

 

[Silver_Is_Money]

It looks like you are reading it correctly. Alkalinity will need to be addressed. Your water is low in total hardness. Your water is also high in sodium. For many styles it may benefit you to use RO water with added mineralization, to avoid your waters alkalinity (bicarbonate). Overall, and in general (this being style dependent), you need more total hardness, appreciably less alkalinity, and about 50% less sodium.

Total Hardness = (2.5 x Ca++) + (4.12 x Mg++)

Your best overall bet for raising total hardness would be the addition of Calcium Chloride, but for some styles (British ales for example) some Calcium Sulfate would also help.

 

[mabrungard]

The sodium isn't too high for brewing, but be aware that you may not want to add much sodium in the future. All the flavor ions (Mg, SO4, and Cl) are quite low and you'll likely want to add salts to boost as you see fit. Alkalinity is high and requires your attention. Acid will be your friend.

 

[ajdelange]

You have correctly identified bicarbonate as the main problem here. It accounts for 98.2% of the alkalinity with about half a percent each from carbonate and, interestingly enough as it's unusual, phosphate. The remaining 0.75% is attributable to H+ ion.

When discussing alkalinity it is much easier to use mEq/L as the unit (for reasons that you will see shortly) than ppm as CaCO3. The conversion is trivial. Multiply ppm by 2 and shift the decimal two places to the left. You have alkalinity of 199 ppm as CaCO3 which is 3.98 mEq/L. In any case, you have almost 4 mEq/L alkalinity and you are going to have to dispose of 90% of that, one way or another, for most beers. The easiest is to dilute with RO water to the extent of at least 3:1. That would get alkalinity down to 1 mEq/L which is generally considered a good place to be though you will still need a bit of acid or sauermalz to get rid of that last bit. If you need to produce or buy 3 gallons of RO water for every 4 you brew with I always observe that you might as well get the 4th gallon and use 100% RO as it lends total control over mineral content.

Second easiest would be to add acid. Lactic and phosphoric are the two used most commonly by US home brewers. You will need about 90% of 4 mEq or 3.6 mEq per liter of water treated and it will result in 3.6 mEq/L lactate (or phosphate) in the mash liquor. For perspective 88% lactic acid is about 11.5 N at mash pH meaning that 3.6/11.5 = 0.31 mL per liter treated would be required or about 4 mL for the typical 3.5 gal mash water that might be used for a 5 gal batch. This probably isn't too much from the flavor point of view. I think you are on the edge in this regard. Phosphoric acid is less flavorful so that consideration might push you towards it rather than lactic.

An intriguing possibility for you as you are low in sulfate and chloride is to use one of their acids replacing the 3.6 mEq/L alkalinity with 3.6 mEq/L sulfate (176 mg/L which is a lot to my way of thinking but certainly not to many others) or 3.6 mEq/L chloride (128 mg/L which is probably higher than you would want to go especially with the high sodium). You might want to split the difference. About perfect for your particular case is the British product (sold in volume as AMS and in homebrewing quantities as CRS) which is an equinormal mixture of the two acids at 3.66N thus you would need very close to 1 mL per L of your water. Practically speaking getting your hands on any of these acids in food grade outside the UK is going to be a problem.

You can get almost the same result (though you won't be able to remove quite as much alkalinity) by boiling the water or by adding lime to it. You will need to get your calcium up above the alkalinity level before you do this, however. The rule of thumb says that out of the 4 mEq/L alkalinity you can drop 3 taking 3 of calcium with it. So if you add 3 mEq/L calcium as the chloride and/or sulfate you would be, nominally, left with the same calcium level as that with which you started but have the alkalinity down to about 1 mEq/L. And, as was the case with the acids, each mEq of alkalinity removed has been replaced by a mEq of chloride or sulfate depending on which salt you used.

Ca at 27 mg/L is 1.35 mEq/L (divide by 20 or multiply by 5 and shift the decimal point 2 to the left) which is, to many people's way of thinking, not enough. If you want more add it before boiling or lime treatment as this often enables removal of bicarbonate to somewhat below the 1 mEq/L alkalinity level.

It should obvious that while lime treatment or boiling give the same result as adding sulfuric or hydrochloric acid it is a lot more work but as you probably can't get your hand on FCC HCl or H2SO4 nor AMS or CRS it is a distinct possibility for you.

 

[cire]

I *think* my water is pretty good other than being relatively high in bicarbonates and low in calcium. Am I reading it wrong?

No, you have it. Now I must confessing there are waters described on this forum which are vastly different to any waters I ever experienced or read of in the UK where I live, but this is another of those. My own experience with natural waters has been that the majority of alkalinity will be associated with calcium and magnesium, the majority of chloride with sodium as well as most sodium with chloride, while sulphate is usually found with calcium or magnesium. Each won't exactly balance with one another, but if they don't by some large measure, as in this case, it can indicate there could have been human intervention. Could some part of your water supply be softened, and if it might, could it be somewhere in your control?

I'm thinking that more likely natural water would be calcium at 75ppm, Mg 4, Na 6, SO4 3, Cl 9 and alkalinity 199, which run through a low efficiency ion exchange water softener could produce what you have. It may well be better with more calcium rather than sodium.

It should obvious that while lime treatment or boiling give the same result as adding sulfuric or hydrochloric acid it is a lot more work but as you probably can't get your hand on FCC HCl or H2SO4 nor AMS or CRS it is a distinct possibility for you.

Brewers Supply Group
Chris German
800 West First Avenue
Shakopee
55379 Minnesota
USA
Telephone: +1-800-374-2739

Are said to be distributors for Murphy and Son.

 

[ajdelange]

Now I must confessing there are waters described on this forum which are vastly different to any waters I ever experienced or read of in the UK where I live, but this is another of those.

There is an infinite number of ways in which ions can combine depending on the geological underpinnings of the water supply, local influences such as agricultural runoff and salt treatment of roads in winter and how the utility treats the water.

My own experience with natural waters has been that the majority of alkalinity will be associated with calcium and magnesium,

That would certainly be expected where most of the mineral content in the water comes from dissolution of limestone or dolomitic limestone by carbonic acid and, of course, that is extremely common.

the majority of chloride with sodium

This is often the case near the sea and where roads are salted in winter. But you will find chloride not associated with any cation where the utility has adjusted pH with HCl.

as well as most sodium with chloride,

Consider the Searless Valley (California) whose biggest town is named Trona (Na2CO3). In regions like that where there were once alkaline lakes (note that OP is near San Diego) I think you will probably find sodium "paired" with carbonate and sulfate. I put "paired" in quotes because the point I am trying to make is that you can't pair ions. All you can say is that the total number of positive charges must equal the number of negative. Did a sodium ion come from dissolved mineral mirabilite (paired with sulfate) or from dissolved trona (paired with bicarbonate/carbonate) or dissolved halite (paired with chloride) or from sodium hydroxide (paired with OH-) added by the utility to adjust pH upwards for mains protection or from sodium hypochlorite (paired with OCl-) added to chlorinate the water or from an ion exchange process (replacing calcium or magnesium)?

while sulphate is usually found with calcium or magnesium.

As calcium, magnesium and sodium are the only three cations found in any appreciable concentration in potable water there is a good chance that sulfate will be found with one of these present. Where there is sodium present, as there would be where groundwater from a xeric region is used in a xeric region (mirabilite present) it shouldn't be surprising to find it paired with sodium (if it is present - it's not in OP's water).

Each won't exactly balance with one another,

In gypseous water i.e. water where there is permanent an temporary hardness (Burton, Dortmund, Viernna) they won't even come close to balancing as the calcium and magnesium is 'shared' between sulfate and bicarbonate.

As a general observation, you cannot tell what salts (minerals) were responsible for a particular ion composition. It's easy enough to determine how much of each of the 7 ions of interest are produced by given quantities of the dozen or so minerals that might be involved but going he other direction is not easy to do as it would, using my numbers, involve solving 12 equations in 7 unknowns.

but if they don't by some large measure, as in this case, it can indicate there could have been human intervention. Could some part of your water supply be softened, and if it might, could it be somewhere in your control?

If one sees a water report with appreciable alkalinity and/or sulfate but no hardness one can conclude that there was intervention (exchange softening) but in this case there is certainly no support for that conclusion. I certainly don't know the details of San Diego's water supply but given where it is located I am certainly not surprised to find a fair amount of sodium in it.

I'm thinking that more likely natural water would be calcium at 75ppm, Mg 4, Na 6, SO4 3, Cl 9 and alkalinity 199, which run through a low efficiency ion exchange water softener could produce what you have. It may well be better with more calcium rather than sodium.

OTOH as I don't know the details of what San Diego does (they were experimenting with desalinization and even treated gray water at one point) I can't say that this is not a possibility. According to their web sites they source 85 - 95% of their water from sources outside the region. They give a list of the operations they perform (the usual sedimentation, flocculation, filtration and pH adjustment) but do not mention ion exchange.

Brewers Supply Group

I'll file that one away for future reference. AMS is not in their catalogue but is, perhaps, available on special order.

 

[cire]

While I don't wish to add to all the pedantry on this forum, I think an infinite number of combinations is a little high. When analysing water we test levels of alkalinity, 4 cations, 4 anions, all else being considered minor and irrelevant. The law of multiple proportions states that when elements form compounds, the proportions of the elements in those chemical compounds can be expressed in small whole number ratios, so really, in the global picture, the potential proportional combinations of those might not be so massive.

A problem I do have is understanding the significant difference between US and UK waters. It rains a lot here, well, it seems that way as it rains most weeks, quite equally across the nation as weather fronts generally pass from one side of this country to the other in part of a single day. We have many rivers, 83% of the world's chalk streams are in Britain and we don't pump them dry before they get to the next tributary, probably because we don't find it necessary. Any soluble deposits near the surface have long since washed into the oceans which are a relatively small distance downstream, so we have no salt flat, instead aquifers with fresh water mixed with some from previous ice ages. Virtually everybody can drink their domestic water supply directly without a water filter and water softening is restricted to the dishwasher and heating. Similarly we can take these waters, treat them simply, they have nothing to remove, alkalinity can be converted in a simple way, and make beer.

 

[ajdelange]

While I don't wish to add to all the pedantry on this forum, I think an infinite number of combinations is a little high.

Pedantry is
"Excessive concern with minor details and rules." (Oxford dictionary).

When analysing water we test levels of alkalinity, 4 cations, 4 anions, all else being considered minor and irrelevant. The law of multiple proportions states that when elements form compounds, the proportions of the elements in those chemical compounds can be expressed in small whole number ratios, so really, in the global picture, the potential proportional combinations of those might not be so massive.

You are under the misconception that because the ratios of ions within a compound are in fixed proportion there must be some limitation on the number of ion mixes that are possible when these salts are blended. This is wrong and, to borrow the OED's example of usage ‘to object to this is not mere pedantry’. What you are failing to understand is that while there are clearly limits on the minimum (0) and maximum amounts of a salt dissolved in a particular water there is no restriction on the number of ratios that the concentrations of a pair of salts exhibit. The ratio could be could be 2 or it could be 400000000000000000/200000000000000001. You may also be under the impression that despite this the fixed proportion within the salts may prohibit certain combinations and thus impose limitations. There are, of course, some limitations. If, for purposes of illustration, we suppose that the only salts available are CaSO4.2H20 and CaCl2 and suppose that the amounts of each that can dissolve are independently and uniformly distributed between 0 and 1 mmol/L then we coudn't possibly have more than 2 mmol/L calcium or chloride nor more than 1 mmol/L of sulfate and both chloride and sulfate will be correlated with calcium. But chloride and sulfate are not correlate. The attached picture shows the results of a Monte Carlo with 500 points. I hope you will be able to see from this that a mix of even two salts can result in a (countably) infinite number of ion concentration combinations.

A problem I do have is understanding the significant difference between US and UK waters.

You shouldn't. Someone else here posted on the geological diversity of the Sceptered Isle and while it is diverse indeed the rest of the world is geologically and climatologically even more so.

 

[mabrungard]

A problem I do have is understanding the significant difference between US and UK waters.

I continue to be amazed that people think their hydrogeologic conditions and water supply are 'unique'. As an engineer solving water problems around the world, I can assure anyone that their conditions are more like other places than unique. The big difference is largely the presence or absence of carbonate rock and soil.

While there is a lot of carbonate rock and soil in England, I can assure you that there is a HUGE amount in the US. English water isn't that unique. In addition, there are plenty of places in England that have almost Pilsen-like water. So its folly to lump 'anywhere' into a single bucket.

 

[ajdelange]

I thought I'd add the sulfate vs calcium scatter plot from the Monte Carlo simulation of No. 8 as it illustrates, perhaps more clearly than the Cl vs SO4 plot, that, given limitations on the maximum amounts of CaSO4 and CaCl2 which can dissolve, there are limits on the relative levels of chloride, calcium and sulfate but that within those limits there are an infinite number of possibilities.