tds-3 - cheap and basic but will give you total dissolved solids reading - just not what they are

 

The water where I live is quite soft so I would like to start making my own water for coffee. I've read @Xpenno 's latest blog post but I would first like to test my tap water. Can you recommend any tests/tools I can purchase off Amazon which measure the content of the various minerals?

By a small portable electric water distillation unit, then distill3.5 to 4 litres of water. Smell and examine what remains in the bottom of the distillation unit. If you added it back to the water you distilled would you be happy to drink the rediluted solution, if yes, then your waters fine. In summer of course things get a lot worse and it might surprise you to see some of the stuff left after distilling! The water companies of course make no mention of any of this. Or you can take the blue pill.

Chlorine content won't be obvious from this test, because the distillation process will lose it, but you should smell it if a lot is there before you start the distillation process.

https://www.makewaterpure.co.uk/?gclid=CIfIgtXL1ssCFc0y0wod4AcKSw

P.S TDS gives you the total dissolved solids that affect electrical conductivity, not all suspensions, colloids, chlorine particulate matter, organophosphates etc..

 

I should've mentioned that I'm looking for something cheap. If that's not available I'll go straight to making water though.

 

I should've mentioned that I'm looking for something cheap. If that's not available I'll go straight to making water though.

Can you get any info from your local water authority? They don't always list everything, but you're mainly interested in dry residue (TDS), magnesium, calcium, PH.

 

A TDS tester should do fine. A local aquarium shop will also have test kits or perform the test for you for a small fee.

 

Good idea. What I was able to find is pH 7.2, calcium http://www.lenntech.com/calculators/conductivity/tds-engels.htm this conductivity translates to 37.9 ppm tds. Does this make any sense?

 

Can you get any info from your local water authority? They don't always list everything, but you're mainly interested in dry residue (TDS), magnesium, calcium, PH.

oops, forgot bicarbonate too..

 

I found something more detailed:

pH: 7.40

Hardness: 0.83meq/l

Ca: 10.6 mg/l

Mg: 2.15 mg/l

Total organic carbon: 2.16mg/l (not sure if this is relevant to bicarbonate)

Conductivity: 97.3 microS/cm

 

Good idea. What I was able to find is pH 7.2, calcium http://www.lenntech.com/calculators/conductivity/tds-engels.htm this conductivity translates to 37.9 ppm tds. Does this make any sense?

Straight from the tap? Then No. Conductivity should be in the range from 200 (really soft) to 1000 (really hard) microS/cm

 

I found something more detailed:

pH: 7.40

Hardness: 0.83meq/l

Ca: 10.6 mg/l

Mg: 2.15 mg/l

Total organic carbon: 2.16mg/l (not sure if this is relevant to bicarbonate)

Conductivity: 97.3 microS/cm

Looks very soft.

 

I found something more detailed:

pH: 7.40

Hardness: 0.83meq/l

Ca: 10.6 mg/l

Mg: 2.15 mg/l

Total organic carbon: 2.16mg/l (not sure if this is relevant to bicarbonate)

Conductivity: 97.3 microS/cm

Looks like a good base, I'm jealous.

Hardness is 35-40 (in mg/l as CaCO3), depending on whether you believe the meq/l or Ca/Mg numbers more, and alkalinity probably about the same going by the pH and conductivity. You can check this using, for example, the API GH/KH test kit widely available on ebay. If you can stretch to it, the Salifert alkalinity test kit is more accurate (for the alkalinity only). You could experiment with adding some more hardness, e.g. an extra 75 (mg/l as CaCO3) would require 1.5 meq/l or 0.75 mmol/l of Ca or Mg. Epsom salt has a molar mass of 246.5, so 246*0.75 = 185 mg/l of that would do the trick. This is similar to the water I'm using at the moment, which I find works well, although I get it by adding calcium carbonate and epsom salt to RO water.

Note, if you look back through the threads you might see that some of us briefly tried much larger quantities of Epsom salt, but without great results.

This though was prompted by an error in the "Water for Coffee" book, the authors were actually meaning to recommend water of much the same makeup as I describe here.

 

I'm thinking of going this way but the SodaStream is rather expensive at the moment: http://grindscience.com/2015/08/making-water-for-coffee-sodastream-method-best-recipe-so-far/

 

This though was prompted by an error in the "Water for Coffee" book, the authors were actually meaning to recommend water of much the same makeup as I describe here.

@GlennV what are the targets they now recommend?

 

I'm thinking of going this way but the SodaStream is rather expensive at the moment: http://grindscience.com/2015/08/making-water-for-coffee-sodastream-method-best-recipe-so-far/

But why? The water coming out of your tap looks like it's pretty much the same as what I get when I add CaCO3 using the sodastream (note I use a little less than half the amount of CaCO3 as Xpenno does in that article).

 

But why? The water coming out of your tap looks like it's pretty much the same as what I get when I add CaCO3 using the sodastream (note I use a little less than half the amount of CaCO3 as Xpenno does in that article).

The measurements I found are a year or two old and I'm not sure if they can be relied upon. I think it will be more consistent if I start with RO water. Plus Xpenno's method has a recipe which makes things easier

Still, it won't hurt to try using my tap water. Let me see if I got this right - I should add 185mg/L epsom salt per liter of brewing water which takes care of the magnesium, right? What about the calcium?

 

@GlennV what are the targets they now recommend?

No idea tbh

The point is that the recommendations in the book, which are presented "as ion" by weight (as are all the calculations in the book) should in fact be interpreted "as CaCO3". This is because the water used for their tests was calibrated using drop tests reading "as CaCO3", not "as ion" as they thought. Hendon has described the mistakes that were made on the water channel of the barista hustle slack. The result of all this that 100/50 water (GH/KH as CaCO3), as recommended in Jim Schulman's insanely long water faq, sits right in the middle of the recommended zone in the book.

 

No idea tbh

The point is that the recommendations in the book, which are presented "as ion" by weight (as are all the calculations in the book) should in fact be interpreted "as CaCO3". This is because the water used for their tests was calibrated using drop tests reading "as CaCO3", not "as ion" as they thought. Hendon has described the mistakes that were made on the water channel of the barista hustle slack. The result of all this that 100/50 water (GH/KH as CaCO3), as recommended in Jim Schulman's insanely long water faq, sits right in the middle of the recommended zone in the book.

That's odd, in the corrigendum 10.10.15 they state that "as CaCO3" is not what they want & that values reported as CaCO3 result in values (such as SCAA recommendations, which is close to Jim Schulman's 100/50), is farther from their ideal zone than originally specified?

I'm not saying that I think there is anything wrong with the SCAA/Jim Shulman ranges (far from it), just ever more confused with every subsequent update on the matter.

 

That's odd, in the corrigendum 10.10.15 they state that "as CaCO3" is not what they want & that values reported as CaCO3 result in values (such as SCAA recommendations, which is close to Jim Schulman's 100/50), is farther from their ideal zone than originally specified?

I'm not saying that I think there is anything wrong with the SCAA/Jim Shulman ranges (far from it), just ever more confused with every subsequent update on the matter.

The correction I refer to was subsequent to the publication of the corrigendum. I've just looked, though, and it's actually fallen off the Slack (which doesn't appear to keep messages for ever). They have promised a second corrigendum, but it's not an ideal state of affairs in the meantime.

 

The measurements I found are a year or two old and I'm not sure if they can be relied upon. I think it will be more consistent if I start with RO water. Plus Xpenno's method has a recipe which makes things easier

Still, it won't hurt to try using my tap water. Let me see if I got this right - I should add 185mg/L epsom salt per liter of brewing water which takes care of the magnesium, right? What about the calcium?

@GlennV I'll be going to the chemist to buy some supplies after work. Do I need both Calcium Carbonate and Epsom salt?

 

@GlennV I'll be going to the chemist to buy some supplies after work. Do I need both Calcium Carbonate and Epsom salt?

You'd need a sodastream to dissolve the calcium carbonate - I'd just try the Epsom salts first. What water do you normally use? I know @Xpenno prefers chloride, so if your chemist has some magnesium chloride you could try that instead - I was suggesting the sulphate as it's easy to find, is non corrosive and I don't think I can tell the difference myself between sulphate and chloride at these low levels (although I've not done careful side by side tests keeping everything else constant).

 

You'd need a sodastream to dissolve the calcium carbonate - I'd just try the Epsom salts first. What water do you normally use? I know @Xpenno prefers chloride, so if your chemist has some magnesium chloride you could try that instead - I was suggesting the sulphate as it's easy to find, is non corrosive and I don't think I can tell the difference myself between sulphate and chloride at these low levels (although I've not done careful side by side tests keeping everything else constant).

Thanks! I bought a package of Epsom salts and will make some water this evening. Usually I use tap water for all my needs - drinking, coffee, cooking, etc. Off to read I go..

EDIT: @GlennV I checked the molar mass of Epsom salt and it varies with its different forms(?). The package doesn't say if it's heptahydrate (which I suppose you're refering to) or not - is there a way I can check? I bought it from a pharmacy and it is sold as a laxative.

120.366 g/mol (anhydrous)

138.38 g/mol (monohydrate)

174.41 g/mol (trihydrate)

210.44 g/mol (pentahydrate)

228.46 g/mol (hexahydrate)

246.47 g/mol (heptahydrate)

EDIT2: Nevermind, the info is available on the website of the company which produces the salt - it's heptahydrate

 

So this morning I had an espresso made with tap water and then another with tap water + 185mg/L Epsom salt. There was no blind A/B comparison, but I tried to keep all parameters the same. The Epsom salt espresso definitely has a more pronounced acidity and more clarity in the flavors. There is a lingering cocoa/chocolate sweetness in the aftertaste which I wasn't getting before. Of course, that might be due to me knowing which espresso was made with which water plus it's a relatively new bean to me

I'll try and do some cupping when I receive my order from Foundry to see if I can still taste a difference. Many thanks to all who helped.

 

I purchased a cheap TDS meter today. My tap water has a TDS of 45-7 ppm and the water I made with 185mg/L Epsom salt is 125 ppm. I'll be looking for a cheap Soda Stream so I can experiment with different Ca/Mg combinations but so far I'm very happy with my new water. I am yet to do a blind cupping/tasting but I am pretty sure I taste the difference.

 

I received my Tetra GH/KH test this morning and measured my water. I doubled the volume of the water sample to get more accurate readings (10ml instead of 5ml so every drop is 0.5° dH). The total hardness is 6° dH (107 ppm CaCO3?) while the carbonate hardness is 0° dH. Yes, 0.. The manual says that the water should turn from blue to yellow but mine was yellow from the first drop. If I recall correctly you need to have some carbonate hardness so what can I do to fix this?

EDIT: Can a mod merge this topic with the main Water for coffee thread?

 

Glad I clicked on this thread!

Great blog by Xpenno, thanks for including the link.

Soda stream on offer (in red only) at Argos right now.

http://www.argos.co.uk/static/Product/partNumber/4447322.htm

I make sole (pronounced "solay") salt solution as a health aid so after reading the blog I randomly put a few drops of this solution into my pouring kettle and made a V60 - which I've never nailed. To my surprise the resultant coffee was really nice and the best cup I've ever made! (I use remineralised RO water).

Now I'm going to have to go the whole hog and try this!

Maybe I won't need the Rafino I just bought...