Accurate Water Testing Kits

JHCCoffee

I would like to test my coffee water for PH, alkalinity, calcium hardness, total hardness, chlorine, chloride, magnesium, iron, etc. I have seen low cost test strip kits, but wonder about their accuracy. On the other hand, I do not wish to spend a fortune on this. Any suggestions on reasonably accurate test kits?

JHCCoffee

@Rob1

Any thoughts on this, Rob1?

Rob1

No, I know nothing about testing for those things specifically. The API freshwater GH/KH test kit is what I use for alkalinity in hardness but that doesn’t give you a breakdown of what the alkalinity and hardness is made up of.

You’re probably looking at sending a sample to a lab, but what use that would be with something that is only subject to safety limits and can change significantly from season to season is questionable….assuming your water is tap water.

Test strips wouldn’t be accurate enough for me testing GH/KH, better off with titration kits and I imagine the same is true for the different things you want to test for.

JHCCoffee

Rob1 @MediumRoastSteam @DavecUK

Hi Rob1, MediumRoastSteam, DavecUK

Firstly, I just want to thank you (and all) for all of your excellent and patient advice and help. I wish there were some way I could give back (I already donated), but you guys know so much more about espresso than I. This is indeed such a friendly and helpful Forum, unlike some message boards that are frequented by trolls and other self-impressed but ungenerous characters.

So, thanks for helping with my often detailed learning questions. And here we go on water:

I about to send off my water for complete testing. I plan two tests: 1) The TWW water (a gallon of RO water from a supplier, mixed with a TWW packet) after mixing but before being filtered by the Lelit filter. 2) TWW water, after filtration through a Lelit filter.

For Test 2, I plan to fully purge the steam and brew boilers by running hot water until it stops (with pre-infusion off). And then use the hot water wand to get the required 1 litre water sample for the test. I presume that my sample will end up as 1 litre of fully Lelit filtered water only. There cannot be any water from “contaminate” sources in this Test #2 sample, such as any water that may enter via the unfiltered OPV hose.

So, am I OK with using the hot water wand to source this test water? If not, I will find a way to pump my TWW water through the Lelit filter for Test 2.

FYI, I have been using the Lelit filter on the TWW water because I do not currently have information on it’s calcium and overall hardness, and because @DavecUK sternly warned me of the many Lelit system consequences of not doing so. :)

However I suspect that the Lelit filter is removing minerals that beneficially contribute to taste. The water tests will provide clear water chemistry information on TWW water, before vs after Lelit filtration. I can then use this information to find the best balance between Lelit machine protection and water taste.

I do fully purge all boilers once per month and also run 50 ml through the hot water tap and 25 mo through the grouphead, before my morning espresso shot.

MediumRoastSteam

JHCCoffee For Test 2, I plan to fully purge the steam and brew boilers by running hot water until it stops (with pre-infusion off). And then use the hot water wand to get the required 1 litre water sample for the test. I presume that my sample will end up as 1 litre of fully Lelit filtered water only. There cannot be any water from “contaminate” sources in this Test #2 sample, such as any water that may enter via the unfiltered OPV hose.

To drain the steam boiler, you can use the water tap yes, but you must make sure that:

ev=1 in advanced settings;
The steam boiler is is on, and temperature is as high as you can, say, 140C;

It will never drain fully. So, no matter what, there will be water left over there. As for the brew boiler, to purge you should draw approx. 500ml of water.

I don’t understand your last sentence quoted above. The OPV (expansion valve) returns water from the brew circuit back to the tank. If you don’t want to do that, simply put that hose into a container outside the tank. There’s no water going into the hose. Only coming out of the hose.

JHCCoffee and also run 50 ml through the hot water tap and 25 mo through the grouphead, before my morning espresso shot.

I understand drawing water through the hot water wand - although 50ml is not good enough if the point is to keep the water refreshed in the boiler. It’s good practice though.

As for drawing water through the group head, there’s no need and no benefit.

CoyoteOldMan

JHCCoffee 1) The TWW water (a gallon of RO water from a supplier, mixed with a TWW packet) after mixing but before being filtered by the Lelit filter. 2) TWW water, after filtration through a Lelit filter.

I don’t understand the point of carrying out this test. The Lelit filter is meant to reduce hardness and prevent scale if the water put into the tank is ‘too hard’. It does that by capturing cations (Ca^++^ and Mg^++^) from the water, but Lelit (AFAIK) does not say what percentage, for how long the filter is effective, and whether it also captures other ions. If it performs a total cation removal (likely!), you end up having water just like you had after an RO process and adding some alkalinity through whatever TWW uses to produce it (citrates?).

If the Lelit filter somehow (magic?) removes only parts of the cations, then the same result can be had simply by adding half (or a third/quarter/whateverth) of a TWW sachet (or one sachet to two gallons) to your RO water and supplementing it with other alkalinity-generating salts if necessary; why use another filter?

The effect on taste you can verify quickly (to some extent - human memory for taste isn’t brilliant, usually); the effect on scaling and/or corrosion would require long-term testing with a consistent water formulation over weeks if not months. The TWW formulation is supposed to be non-scaling, too, so the concern should be less than with other remineralisation formulas.

If you really want to have lab tests done on TWW and on whether it scales or improves flavour or not, you are much better off asking for a quali/quantitative analysis of the TWW formula, rather than monkeying about with an intermediate filter.

Rob1

I’m also confused about your plans to test the water….

JHCCoffee FYI, I have been using the Lelit filter on the TWW water because I do not currently have information on it’s calcium and overall hardness,

The calcium alone doesn’t matter. The TWW give you Calcium and Magnesium, the hardness of these two expressed as CaCO3 is what you need to know. A freshwater API drop test kit will tell you the hardness of the water in mg/l as CaCO3. You also need to know alkalinity from carbonates, which unfortunately the drop test kit will not tell you as TWW use both citrate and bicarbonate to get alkalinity and citrates have a different titration endpoint, so you can’t use the drop test kit effectively…..though TWW offer different sachets so maybe they don’t for the one you’re using - ingredients will be listed.

Pulling water through the steam boiler is not a good idea. Put a blank disc in, run a shot as if you’re backflusing, and collect a sample from the return hose on the OPV. Though this is the part that confuses me as I don’t understand why you’re going to the trouble of getting RO water and TWW sachets AND then filtering it. I’ll be surprised if the Lelit filter is doing anything more than replacing Ca and Mg with Na.

I think Coyote has a good idea above requesting an analysis of the sachet contents rather than the result after adding it to RO water, unless maybe the RO water is totally pure and you can get a cheaper analysis of a water sample.

JHCCoffee

Thanks all. Appreciate your comments and suggestions.

I was just curious as to what TWW does to the water chemistry, in this case RO water. I could have the TWW powder tested, but: a) it would be alot more expensive to do, and b) it would not show the water chemistry end result, namely the chemistry of TWW when it is mixed with the RO water produced here in Toronto (I currently buy the RO water, as I have not yet set up an RO system in my home; it’s something I would need my wife to agree to, especially as it would take up cupboard space).

I have been using the Lelit filter out of pure nervous caution (given DaveC’s admonition about potential Lelit system impacts, apparently not just scaling but also on sensors and valves, etc.). But I agree that if the TWW treated RO water has (after testing) a reasonably safe chemistry, it might be preferable to use that TWW water without a Lelit filter than with one. IF I prefer the taste (assuming I can detect a taste difference) from say BWT filtered water or other water options.

Fyi, I had earlier made my own water using a recipe provided by one of the espressos pundits (Grind Science), which included calcium carbonate and sea salt, which I thoroughly dissolved in carbonated RO water (using a soda stream carbonation device) and then let sit for a day, to let any undissolved powder settle. I then mixed this with RO water to achieve a TDS target, and filtered that through a BWT filter to remove any undisolved powders and to add magnesium (which apparently the BWT filter does). I targeted a TDS (after filtration) of about 165. Grind Science said the recipe results in 100 to 200 ppm total hardness, including 60 to 120 calcium hardness (ppm?) and 40 to 80 ppm magnesium. It apparently had a PH of 6.5 to 7.5. So they said. It did then taste pretty good (according to my notes); I had liked the mouthfeel and preferred it to BWT filtered tap water. Then my Breville DuoPro died of supposedly unrelated causes, and I bought the Lelit. I do wonder about the merits of this particular water recipe vs its unfiltered risks (ie without Lelit filter). However using TWW packets is much much easier.

MediumRoastSteam

JHCCoffee But I agree that if the TWW treated RO water has (after testing) a reasonably safe chemistry, it might be preferable to use that TWW water without a Lelit filter than with one. IF I prefer the taste (assuming I can detect a taste difference) from say BWT filtered water or other water options.

If you are buying RO water already - assuming this is for safe human consumption rather than other purposes - why not just add some sodium bicarbonate to the water as per instructions in this forum and completely ditch the Lelit filter? I’m assuming you are using your current tap water with the Lelit filter.

As said before, I don’t get the idea to use the Lelit Filter with water you are effectively making yourself. Short of replacing magnesium and calcium ions with sodium, what’s the point? Seems a very expensive and wasteful way to go about things. But if that’s what you want to do…

JHCCoffee I have been using the Lelit filter out of pure nervous caution (given DaveC’s admonition about potential Lelit system impacts, apparently not just scaling but also on sensors and valves, etc.).

Lelit filters are not magical nor Lelit has some special machine system. The filter is a filter, and the Lelit machine is an espresso machine. Use hard water with an espresso machine and it will eventually be damaged. The more complex a machine is (e.g: a dual boiler) the higher is the likelihood of getting damaged as it has more pipes, paths, restrictions and valves. When one gets clogged up, the machine is effectively broken. For instance, if you compare it to something like a Gaggis Classic which is a lot simpler, it’s a relatively easy thing to simply descale the machine every so often.

Rob1

JHCCoffee

If you know what is in the TWW and you can get an accurate measure of the contents in mg/l or eveb just % of total mass then you can easily calculate the composition of the water and understand exactly what you’re adding. Surely the RO water comes with some kind of spec sheet, if not the company producing it should be able to tell you what is left over.

The grind science recipe makes no sense at all to me. If you want Mg in the water you can use Magnesium hydroxide instead of calcium carbonate. If you want some Ca you’ve got a choice of a number if different salts, most common being Calcium chloride. You could also just dissolve both Calcium carbonate and Magnesium hydroxide together. You can get sodium from sodium chloride or sodium bicarb easily. Filtering water remineralised to contain Calcium bicarbonate to exchange some Ca with Mg is a bit wasteful/inefficient and guarantees inconsistency. TDS really doesn’t matter and exchanging Ca for Mg doesn’t stop scale, you just get magnesite instead if limestone.

CoyoteOldMan

I wrote a long reply, and then my computer crashed… so I’ll just add what I hope doesn’t sound like a snarky comment, as Rob1 and MediumRoastSteam have covered pretty much the other points I wanted to raise.

JHCCoffee a recipe provided by one of the espressos pundits (Grind Science)

This sounds more like alchemy and magical thinking than chemistry… but it’s definitely a good recipe for scaling, with 100 to 200 ppm between Ca and Mg!

Cuprajake

If you wanted to test your water, some marine aquarium companies offer ICP testing for ro water like Triton, you buy a kit and send it away

MWJB

CoyoteOldMan Grindscience is Xpenno from CFUK, less active in the coffeesphere lately, but as he notes,“The water ends up at about 120 mg/L TDS, 120 mg/L Carbonate Hardness and 60 mg/L alkalinity (2:1 ratio naturally occurs when Calcium Carbonate dissolves in the acidic water).” This is in the recommended range for boiler water according to most sources for the last 20 years Not saying there isn’t ways to do it better, but he’s on the ball here.

Cuprajake

Giphy - content GIF

CoyoteOldMan

MWJB It’s not so much the result, as the method…

Rob1

@JHCCoffee

I’ve found the recipe you were using on grind science under the Soda Stream method. They mention making a concentrate in 1l of water and then adding 300-500ml to 5l water to make the brewing water. Their numbers are really weird here, 300-500ml is a huge difference. Adding CaCO3 to water and dissolving as much as the CO2 allows is also really odd - why not just add it if it doesn’t all dissolve then carbonate a second time, that way you know what you’re working with….anyway…I averaged the figure so I calculated the result of 1.5g CaCO3 completely dissolved in 1l and then 400ml of that added to 4600ml to make 5l brew water:

120mg/l Hardness

60mg/l Alkalinity

Just about 10mg/l Sodium and 15.5mg/l Chloride + impurities in the sea salt.

The 120mg/l Hardness comes from 48mg/l Ca.

What Ca and Mg you end up with after filtration doesn’t matter too much, hardness should stay the same.

I also realised there’s a flaw to my spreadsheet remineralisation page for anybody trying to calculate alkalinity purely by dissolving carbonates or hydroxides with CO2 as there’s no way of showing the transformation of both into HCO3 and the effect it has on alkalinity, you just have to know and account for that yourself in advance so I’ll try and figure out how to fix that.

JHCCoffee

Rob1

Thanks for exploring this, Rob1. It was fairly time consuming to make that recipe. It then tasted good though. Its now history.

Fyi, I just today dropped of a litre of TWW water at a leading Toronto water chemistry testing company, who will provide a comprehensive water chemistry analysis, at a quite decent price. I expect to receive results in a week.

Stay tuned for TWW water chemistry unveiled. The only variable will be that Toronto RO water likely has slightly different water chemistry than other cities, as RO water still has residual dissolved solids (28 ppm in my RO water). A test using distilled water would have been more revealing. But then I am/will not be using distilled water to make my coffee water. I will share the test results when received and will welcome your thoughts on it. Assuming that the test results confirm safe useage (without a Lelit filter, which I agree would be pointless), I will look forward to taste testing it against other safe opinions suggested in this forum.

Rob1

Oh MWJB posted while I was wondering how I could fix the spreadsheet 🤣 Not sure it’s really possible without some coding or something that’s beyond me. I’m just going to add another note….one more can’t hurt.

CoyoteOldMan

Rob1 Happy to code things… I’ll take a look at your note, and see if I can either devise some in-cell logic, or a script, if you don’t mind me doing that.

MediumRoastSteam

Rob1 Not sure it’s really possible without some coding or something that’s beyond me

Rob - I can help you with coding if you need anything. I’ll drop you an email and then you can email me if you want. 👍

Edit: just realised afterwards you now have two offers. 👍😊

CoyoteOldMan

JHCCoffee Looking forward to seeing the lab results!

MWJB

JHCCoffee Stay tuned for TWW water chemistry unveiled.

Was this ever a secet? I recall TWW being quite open about their earlier recipes at least.

CoyoteOldMan

MediumRoastSteam Except that yours comes from a competent person - I’m a dabbler! (Especially with JavaScript - VBA, bad as it is, at least I know well) 😁