Total hardness test kits from Hach appear to be highly regarded (for instance, as per Peppersass' post here, but they seem to be difficult to source in Europe. Some sellers on Amazon.com do ship to Europe, but at a prohibitive cost. Has any fellow European been able to find something similar to the Hach kits, but readily available on this side of the Atlantic?

I'm not in Europe and don't have much to add, but will post anyway because I hate seeing zero replies ‒ hopefully this might trigger a followup from someone in Europe.

Hach appears to sell worldwide ( https://www.hach.com/global-distributor-support ) but for European locations they require a 'contact us' rather than displaying prices and order forms. To the OP, have you tried that to no avail?

For coffee purposes I think you can save money and get adequate results using the very inexpensive API Fishcare GH and KH kit. It's inferior to the Hach kit, especially the hardness kit in quality and documentation. For one thing, the Hach 5B kit lets you add the full amount of color indicator first before adding the EDTA titrant, which should work better at low hardness levels. The API kit has both in the one titrant bottle, which makes it simple but I think can be a little hard to read when your hardness is below 30 mg/L.

For both kits you can get more precision by cheating up the sample volume. For example, with the API kit if you get yourself some bigger test tubes and use a 10ml (rather than 5ml) water sample, then each drop of titrant corresponds to a half German degree of hardness (in CaCO3 equivalents, that gives you precision of about 8.9 mg/L hardness rather than the usual 17.8 mg/L)

Thanks for your reply, really appreciated!

I ended up ordering this kit from Amazon Germany:

https://www.amazon.de/gp/product/B01LBCEPVA/



Hopefully I'll be able to figure out how it works (if instructions are only in German). It looks like you're putting droplets of the supplied liquid into a set volume of water until the color changes. That would be similar to what the Hach kit does, right?

domi wrote:It looks like you're putting droplets of the supplied liquid into a set volume of water until the color changes. That would be similar to what the Hach kit does, right?

Yes, but this one looks a lot more like the API Fishcare GH kit. One reagent bottle contains both an indicator and the EDTA titrant, and goes from yellow to green at the endpoint, with each drop corresponding to 1 °dh in a 5 ml sample. This Grunbeck kit looks a little better than the API kit because they give you a test vial that will take larger samples if you want to cheat it up for better precision. It's cheaper than the Hach kit would be, and looks like a reasonable choice. The Hach kit differs in that you put in a fixed amount of an indicator dye plus buffer reagent, then add the EDTA titrant drop by drop until the color goes from pink to blue.

P.S. Here's a nice concise instruction video for that Grunbeck kit: