CoyoteOldMan No - first step produces a litre of concentrate (so you can measure fairly accurately how much bicarbonate you are adding, instead of going into fractions of a milligramme). The second step dilutes the concentrate to what is actually needed for brewing.

If I prepare 1L of mineralised water with the correct contents of minerals, why do I need to dilute it before using it for brewing? I feel myself very slow in understanding this. But I will get it when I use the system. :)

    The steam is evaporation.

    As you evaporate water to get steam the water left gets stronger, and stronger.

    The steam is what you would make distilled water from if you let it cool. So all the bad stuff is left in the boiler. Do this enough with bad water you get scale.

    Re the sodium carbonate. Don’t use that it’s too strong. That was just my question

    Decent De1pro v1.45 - Niche Duo - Niche Zero - Decent is the best machine ever made -

    Knluk If I prepare 1L of mineralised water with the correct contents of minerals, why do I need to dilute it before using it for brewing?

    If we take sodium bicarbonate as an example, to get the correct level of alkalinity you want 67mg / litre of zero water. This is a tiny amount and almost impossible to weigh out accurately. Making up 5 litres with 320mg is easier to do. Alternatively you can make up a concentrate to use

    Knluk KHCO3 (potassium bicarbonate) - 80 mg/l - for avoid scaling and if use sodium bicarbonate can also enhance taste?

    The purpose of potassium (or sodium) bicarbonate is not to “avoid scaling”. Water for brewing coffee needs some alkalinity to taste good (and some alkaline buffer will also help with corrosion - pure water can become acidic by absorbing CO2 from air). However, potassium or sodium bicarbonate by itself will not create scale.

    Knluk the Magnesium can help avoiding scaling

    Quite the opposite, unfortunately. Magnesium and calcium salts are likely to cause scale. Magnesium (carbonate) is more benign than calcium - partly because it doesn’t tend to ‘stick to itself’ as much as calcium carbonate does, and partly because it creates less amount of scale to start with. However, water containing (bi)carbonate ions and calcium or magnesium ions in quantities generally believed to be ‘good’ for making coffee will scale.

    Knluk Does steam boiler has a scaling point? How can I check the point? Reload with pure water? Does it need to be mineralised pure water?

    Dissolved minerals in a steam/service boiler will tend to get more concentrated over time, as steam is extracted but none of the minerals/salts in the water. If you use the spreadsheet that @Rob1 has created, it has a page to help you predict ‘when’ it will scale, depending on your water characteristics and usage, but the TL;DR message is “it will scale if you use calcium and/or magnesium”.

    It is a good practice to dilute the minerals by discharging some mineral-rich water regularly (every day) and replacing it with (at least) brewing water. Even better is to empty the boiler regularly, and re-fill it with de-mineralised water.

    Knluk the 12-16 L in 3 days?

    A day.

    We are two mostly. We also draw about 10-12L a day - coffee, tea, smoothies, drinking and cooking!

    Thanks again all! I did not expect the water is much more complicated than coffee. I have a bit more understanding on the water now.

    So, I think my workflow should be:

    Hard water > water softener > softened water > zerowater > prepare mineral concentrate and add to the water > use the mineralised water within 3 days (While keep some water in the zerowater between use (btw do you use this water?))

    Re mineral:

    Option 1: make it simple

    • KHCO3 (potassium bicarbonate) - 80 mg/l

    Option 2: for best taste esp for dark roast

    • MgSO4 · 7 H2O (Epsom salts) - 148 mg/l

    • KHCO3 (potassium bicarbonate) - 80 mg/l

    • NaCl (table salt) - 25 mg/l

    For both options, there is no scaling issue but need to replace all water in the boiler from time to time when the mineral concentration built up. May I ask what should be the interval here? Say every month?

    Also, before I get a lever machine, for Robot, I plan to use zerowater after I finished the volvic I stock up. As there is not boiler in Robot (no scaling issue), should i add the following for taste enhancing?

    • MgSO4 · 7 H2O (Epsom salts) - 148 mg/l

    • NaCl (table salt) - 25 mg/l

      Knluk Option 1: make it simple

      Option 3, keep it very simple:

      • 80mg/L or 100mg/L (I use the latter, my tastebuds cannot taste the difference)
      • Drain the steam (aka service) boiler every 2 months. When you do, keep the drained water. Let it cool down to room temperature and measure the TDS. Adjust the interval accordingly.

      also worth noting, potassium and sodiums will give different tds readings i believe

      Decent De1pro v1.45 - Niche Duo - Niche Zero - Decent is the best machine ever made -

      Knluk So, I think my workflow should be:

      Hard water > water softener > softened water > zerowater > prepare mineral concentrate and add to the water > use the mineralised water within 3 days (While keep some water in the zerowater between use (btw do you use this water?))

      If you are planning to use a Zero jug, there is no benefit in softening the water before de-ionising it. Unlike an RO membrane, the resin won’t ‘care’ whether it captures a sodium or a calcium atom.

      Yes, I would use the water from the jug, if you keep cycling through it every couple of days. Not if it’s been sitting there for a week!

      Knluk As there is not boiler in Robot (no scaling issue), should i add the following for taste enhancing?

      Water alkalinity plays an important role in taste, so I would add the bicarbonate in the Robot as well.

        CoyoteOldMan there is no benefit in softening the water before de-ionising it.

        No difference for the filter life too?

        I have this 3M filter too but forgot the last time we changed the filter :(((

          Knluk No difference for the filter life too?

          Nope. At least, not if your softener is a typical ion-exchange softener.

          Please 🙏 help to confirm the following is okay🙏🙏🙏

          Epsom salt

          potassium bicarbonate

          Table salt: (is Himalayan salt okay)

          Epsom salt and bicarb - perfectly fine. Himalayan salt is also probably fine (it contains a bit of iron, hence the pink colouring, but so little that I don’t think it will affect the taste of anything), but it’s flipping expensive.

          https://www.sainsburys.co.uk/gol-ui/product/salt-pepper/sainsburys-cooking-salt--polybag-15kg <– this is £1/kg
          https://www.sainsburys.co.uk/gol-ui/product/bigger-packs-208331-44/fudco-himalayan-pink-salt-500g <– this is £6.30/kg

            OK so the need to use the water within 3 days is completely new to me. I’ve been storing remineralised Zerowater for my Minima for up to a few weeks at a time before using it in my Minima. I take it this is a bad idea? I would have thought it would be fine since it is all being boiled via the brew - boiler and steam boiler?

              No salt. Avoid chloride. If you want sodium but want to keep it at scaa recommended 10mg/l use both Potassium and Sodium bicarb to get your alkalinity to 40mg/l - you can go higher or lower with alkalinity if you want but 40 is a good start. No need for hardness, but if you really want to try it and think it makes enough of a different to complicate maintenance do what you want…you have a robot to test on to make it easier. Magnesium isn’t any better than Calcium for scaling.

                dutchy101 If you aren’t getting smells or colours in the stored water, it’s probably OK. The only way to know is to do a microbiological exam, as presence of bacteria/algae/protists would be the issue. I don’t think “3 days” is a hard limit…

                  Rob1 hi Rob, good to have your input. As mentioned above, I am hopeless for chemistry. But would love to hear your water recipe? I will try on my Robot but the main goal is optimzing the performance and minimising scaling on a boiler machine.

                  • Rob1 replied to this.

                    CoyoteOldMan

                    I’ve been doing this now since February and haven’t died yet, so hopefully all is OK. I have a Skuma RO unit coming in October, when I will be changing how I do things.

                    Every time a water discussion comes up on here, I feel like I go straight back to square 1 in terms of my understanding of things - lol. Perhaps I might shift to a system of only making up just 1 × 5 litre batch of water at a time until the Skuma arrives as opposed to the 2 × 5I have been making over the last 6 months.

                    The water is certainly not discolouring, nor does it smell so hopefully it has all been OK so far.

                    @Cuprajake - how long do you tend to make up and use your concentrate for?