This is what the osmio zero adds back (from their website)

The final filter in the system contains calcium and magnesium active ceramic balls. They have the effect of adding around 20-30 ppm in total to remineralise the water.

I will just use this and try not to overthink it all 👌

caffeinated-carp

Scaling and corrosion are both dependent on temperature, alkalinity, and hardness.

Water that scales at 125c might not at 105c or 25c. You’ll see the langelier saturation index (or a modified version) telling you a water spec is corrosive at room temp but scaling at your service boiler temp. So no, there’s no perfect solution.

You can remineralise water to an appropriate alkalinity (e.g 40-60mg/l) which will help prevent corrosion. Corrosion is caused by more than just a lack of hardness and alkalinity, and depends on boiler material.

Would not use Ashbeck. Low alkalinity and over 10mg/l chloride and sulphate, so not great.

      MediumRoastSteam Well that sounds easy, what’s with all the mad water recipes? Reading here you have the “rao/perger” recipe:

      • 5 g epsom salt (MgSO4•7H2O)

      • 2 g MgCl2•6H2O (hexahydrate) or 1 g anhydrous MgCl2

      • 1.5 g anhydrous CaCl2 or 2 g CaCl2•2H2O (dihydrate)

      • 1.7 g baking soda (NaHCO3)

      • 2 g bicarbonate potassium (KHCO3)

      That seems a little complex to me :)

      Rob1 Would not use Ashbeck. Low alkalinity and over 10mg/l chloride and sulphate, so not great

      Hm ok, although apparently at least no longer corrosive?

            caffeinated-carp Well that sounds easy, what’s with all the mad water recipes? Reading here you have the “rao/perger” recipe:

            Nothing ‘mad’ about it, it’s a little more KH & GH than Ashbeck at 40mg/L alkalinity and close to twice that value in GH, pretty conservative/typical a recommendation really. You’re getting a bit fixated with the journey & phraseology, rather than the destination.

            We call water ‘water’, calling it dihydrogen monoxide is just a different spelling and a few more syllables, but not as complex as driving a car, or setting up a smart TV :-)

              caffeinated-carp Well that sounds easy, what’s with all the mad water recipes? Reading here you have the “rao/perger” recipe:

              No idea. I’m just telling you what I’ve been using, tastes good (for espresso) and will not cause problems in your espresso machine. 👍

                Will give it a shot. Apologies for all the questions, it’s a bit of a step learning curve when you previously just turned on a tap :)

                Per my other post, look here, there is link to a direct dosing spreadsheet that makes it easy to start playing with different waters given your reservoir size and just simple bicarb and Epsom salts

                  caffeinated-carp Hm ok, although apparently at least no longer corrosive?

                  I don’t know if the specs have changed. It’s corrosive last I checked. If the alkalinity is higher now then maybe not.

                    caffeinated-carp 5 g epsom salt (MgSO4•7H2O)

                    2 g MgCl2•6H2O (hexahydrate) or 1 g anhydrous MgCl2

                    1.5 g anhydrous CaCl2 or 2 g CaCl2•2H2O (dihydrate)

                    1.7 g baking soda (NaHCO3)

                    2 g bicarbonate potassium (KHCO3)

                    That seems a little complex to me :)

                    What’s odd about it is they’ve specified anhydrous forms of everything but the MgSO4 and named Sodium bicarbonate baking soda. Also, they have you mixing the minerals in one concentrate causing salts to precipitate (probably Calcium sulfate).

                    The resulting water spec would be:

                    26.1mg/l Mg
                    15.9mg/l Ca
                    9.26mg/l Na
                    15.63mg/l K
                    38.85mg/l SO4
                    37.79mg/l Cl2

                    40.15 Alkalinity
                    147.18 Hardness

                    Their instructions (from what I could make out) are to make a 200ml concentrate and add 4ml to 1000ml.

                      So I’ve decided to go for the zero water jug, at least initially. Got it today, used the TDS meter and seems my tap water has a reading of 114 which seems quite good from what I can tell. Filters should last a while at least

                      Just made up the first batch of water after running out of Ashbeck. I ended up following the barista hustle recipe 4 using the calculations in the Direct Dosing Recipe Picker & Calculator which seems to be created by people from the EAF discord forum. Awesome spreadsheet I must say, I hope the calculations are correct!

                      I made it up using direct dosing in to my old 5l ashbeck bottle using baking soda and epsom salts, thus these were the options I had from that spreadsheet:

                      I choose the Barista Hustle 4 recipe because actually, of all the recipes it was the only one that fell within La Marzocco’s spec:

                      It’s probably being over the top to ensure I meet their spec, but hey… they do say it would invalidate your warranty!

                      All seemed fairly easy, a bit of a faff measuring the ingredients, and it sucks with the zero water jug to have to fill and empty 3 times but I’ll get used to it I think.

                      I ran enough through the service and brew boiler to purge them. Trying a coffee with it now, seems nice enough.

                      Apparently the TDS (according to ChatGPT because I’m no good at working all this out yet) should be 134 ppm and the zero water meter read 105 (still within LM spec anyway), ChatGPT informs me that my TDS meter is probably not very good.

                      Out of interest, what tests does everyone use to measure GH, KH and pH? As far as I can tell the best way to do GH and KH is a dropper kit, people have mentioned these ones before:

                      For testing ph, any recommendations? Just go for the API ones or can you just go for any old test strips?

                        caffeinated-carp I am not dedicated enough for this :) - but I used a basic TDS reader just to see the overall numbers - though I realise thats not showing any detail. I also picked up a dip test from Amazon. Again I believe the drop tests are the best.

                        I used the dip tests just to see that the output from the Osmio was “working”. Now I just fill and forget.

                            MattH I’m not sure I’m dedicated enough to be honest! Time will tell if I keep up with this. I feel like a mad scientist…

                                caffeinated-carp I’m not sure I’m dedicated enough to be honest! Time will tell if I keep up with this. I feel like a mad scientist…

                                Get a buiness card, cut a strip 5mm wide measure 5mm from the bottom, make a line and bend into an L shape, to make a little scoop. Scoop from a pot of Bicarb and add to 2 litres of RO water…place in machine and get on with your life.

                                Contact me

                                    DavecUK yeh that’s probably easier :D although admittedly whilst this stuff can drive me insane i do enjoy a good process :)

                                    so you’re reckoning that a 5 × 5mm square will result in the right amount of bicarb basically for 2 litres worth?