Rob1 You are right I was confusing the two. still on my journey of learning.
Keep the Osmio Zero water (without mineralisation)
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coffeealex Could i do the same mix on pure RO water? Does the saline solution Keep?
No (theoretical) difference. Some people find a difference in flavour between demineralised water through RO, de-ionisation or distillation.
The saline solution keeps fine in a closed bottle in the fridge (1 month +) - nothing to spoil… and difficult for algae/bacteria/fungi/protists that accidentally fall into it to multiply in the cold and dark without nutrients.
CoyoteOldMan In trying to keep this simple would this scenario work : Lets assume I have a starting point of 0 tds ( I have removed all minerals etc say with zero water) At this point i have scaling under control but corrosion/ taste could be a problem. So I add bicarbonate of soda at 80mg per litre. Now I have both scaling and corrosion in check as I have added an alkalinity buffer to stop the ph becoming too acidic. Surely this would work? At this point is flushing of the service boiler still required as mineral content is very low meaning scaling is unlikely?
coffeealex - adding 80mg/L of sodium bicarbonate works. This will prevent corrosion, as NaHCO3 will act as a buffer. In addition, it won’t scale, as it does not contain magnesium or calcium in its formula.
And yes, you still need to refresh your service boiler periodically, by drawing a mug of water weekly and/or a full refresh every 6 weeks or so, check TDS to keep tabs on it. Like any dissolved solids, it will be left behind in the boiler as you draw steam out, which is pure (distilled) water.
CoyoteOldMan The saline solution keeps fine in a closed bottle in the fridge (1 month +) - nothing to spoil
I keep my concentrate in a cool, dark place, but not the fridge. There’s no smell or anything after two months. I however use distilled water so any organic form is boiled to death anyway.
MediumRoastSteam Thank you, makes total sense
coffeealex “Mineral content” (TDS or dry residue) and “probability of scaling” are not the same thing. You could add a lot of sugar to water (more than the weight of water!), and it wouldn’t scale at 130 °C. Heck, you could add quite a lot of copper sulphate, and it wouldn’t scale.
For scale to form you need Ca and/or Mg and (bi)carbonate (or sulphate, but far less likely) ions in solution. If you only add bicarbonate of sodium or potassium, there is no Ca or Mg, so scale will not form.
Flushing is still required as at some point, as bicarbonate salts convert to carbonate with heating, and carbonate solutions can be corrosive. Do you need to flush frequently? No, probably once every few months - and that’s largely out of caution.
17 days later
Personally I think as far as Oz is concerned, they should have gone the way of Skuma, by having a choice of mineralised/demineralised water by just pressing a button and not having to use an empty cartridge. Surely a simple bypass of the cartridge in the piping would give that choice. Then if you wanted mineralised water you press one button or demineralised you press another or hold the same for longer.
Or have a two cartridge system. One exclusively for espresso machines by not using magnesium or calcium carbonate and another with the minerals for taste. The best of both worlds
16 days later
My Minima is turning up next week and I’m thinking of getting the Osmio Zero to use in the brew and service boilers.
Am I right in thinking that with the Osmio Zero will purify and remineralise my tap water with no other intervention needed, I shouldn’t get any scale?
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Verion There are many water threads on this forum. Please spend some time reading them. One example is here
https://coffeetime.freeflarum.com/d/1105-accurate-water-testing-kits
My OZ experience:
If you manage by regularly drawing a cup after steaming and a monthly full flush, you should be able to minimise the risk.
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Based on my experience with the Evo Leva (same boilers as the Minima), I’d suggest the simple additional step of drawing around a cup of hot water from the service boiler after steaming milk when using the Osmio Zero and the remineralisation cartridge.
I’ve done so for over a year and the TDS of the hot water (after letting it cool down) stays stable at about 55 ppm… and thus I haven’t felt the need for a monthly full flush but YMMV
I have a cheapo “TDS-3” meter bought from less than £4 on Amazon.
While I don’t know how accurate it is, I get distinct but consistent reading over time when measuring tap water (upper 200 ppm), water straight from the Osmio (30-40 ppm) and from the service boiler (~55 ppm).
Also, get a drop kit, measure the GH and KH of your water from the boiler at room temperature. Test on a sample of 20 ml or 40 ml for each test, multiple 17.9 by number of drops and divide the output by 4 (if 20 ml) or 8 (if 40 ml). You can do it on your monthly full flush.
So my OZ turned up to today and it’s set it up and ready to go.
Testing with my £6.99 TDS meter from Amazon, regular tap water at room temperature reading is around 409. OZ water at room temperature is around 49.
That’s quite a drop of 88%.
I need to get the KH/GH test kit from my local aquatics supplier, but the water looks like it’s in a good place for when my Minima turns up.
10 months later
Hi all. I didn’t want to start a new thread so hoped I’d get an answer here……..I’m looking to buy an OZ, for when my Minima arrives. I understand the need to sanitise the OZ but can’t get my head around why it would need descaling (as mentioned in a this and other OZ threads) could anyone answer my (maybe stupid) question please?
P.S I live in a fairly soft water area.
Thanks
Al
