I’ve dropped down the rabbit hole of making my own water after using Waitrose Lockhills for a while. My local water is terrible, enough to scale a kettle within a few uses and I’m looking to get a decent espresso machine in the next few months (a Bianca if I can talk myself and the missus into it!) so I want to start off from a good place.
I’ve read the various discussions about water on lots of different forums including the Barista Hustle recipes and I’ve looked at Rob1’s hardness spreadsheets and MWJB’s mixing spreadsheet (thanks very much both for your work on those). I’ve played around with the hardness spreadsheet and I’m not sure I completely understand it. If I put in 40.1 for Bicarbonate and 68.6 for Magnesium (the SCA recipe if I’m reading it right) I end up with an alkalinity of 32.88 but a hardness of 282.5 which seems like a big number. The LI is .16 but I have no idea if that is very high or “normal”? My Zerowater TDS reading from my tap water is 350 for what it is worth - probably very little I know.
The second and main question is, where do people get food grade Epsom Salts from? I can see it is available from Amazon but I’m leery of ordering anything “food grade” from there as I have no idea where is has been manufactured or whether there are any contaminants in it. Are there any shops on your average UK high street where you can buy it? Rightly or wrongly I presume that if I buy it down my local shop it is probably subject to some sort of regulation (I’m probably naïve!) whereas with Amazon who knows. I’ve read enough Amazon horror stories with toys etc. to put me off from buying food supplements from there.
Maybe I’m just better mixing it with my tap water (very hard, I live in Bucks) or diluting it with a particular bottled water? Sorry I’ve looked but haven’t come across a ZeroWater mixing chart, I appreciate it isn’t dissimilar to distilled though.
Thanks for any advice