sluflyer06 wrote:Thank you for that, is not actually a little too low or is that still good for flavor?

Per most recommendations, that keno recipe does come out a little low in hardness. For example, the current online La Marzocco USA installation guide for your machine recommends 70-100 mg/L. (That is a bit high compared to some recommendations. See this chart: Good references on water treatment for coffee/espresso.)


What you could do would be to mix the bicarbonate concentrate in one bottle, and the magnesium sulfate (Epsom salt) concentrate in another. Then you could experiment. 2 or 3 teaspoons of the Mg concentrate would put you at 40-60 mg/L hardness, which is close to what they used at the last WBC competitions. 5 teaspoons would put you up near 100 mg/L - the Matt Perger recipe. But beware that the Perger recipe would give you a lot of sulfate (96 mg/L) which might be a corrosion concern. At one time La Marzocco recommended less than 50 mg/L sulfate.

sluflyer06 wrote: I'm currently using RO water from store, but its so filtered that sometimes my machine doesn't see the water in the reservoir and i have to add 1oz of tap water to get it to see it.

You want to get away from doing that. Not just for taste reasons - nearly pure RO would be a bit corrosive.

homeburrero wrote:Per most recommendations, that keno recipe does come out a little low in hardness.

Yes, agree if you are using it with RO or zero TDS water. I'm using it with filtered low TDS water, so the hardness from that plus the extra (albeit small) amount from this formula puts me into the recommended range. Like you note you wouldn't want to add too much Epsom salt to make up the hardness because of the potential of sulfate corrosion.

homeburrero wrote:Per most recommendations, that keno recipe does come out a little low in hardness. For example, the current online La Marzocco USA installation guide for your machine recommends 70-100 mg/L. (That is a bit high compared to some recommendations. See this chart: Good references on water treatment for coffee/espresso.)


What you could do would be to mix the bicarbonate concentrate in one bottle, and the magnesium sulfate (Epsom salt) concentrate in another. Then you could experiment. 2 or 3 teaspoons of the Mg concentrate would put you at 40-60 mg/L hardness, which is close to what they used at the last WBC competitions. 5 teaspoons would put you up near 100 mg/L - the Matt Perger recipe. But beware that the Perger recipe would give you a lot of sulfate (96 mg/L) which might be a corrosion concern. At one time La Marzocco recommended less than 50 mg/L sulfate.

You want to get away from doing that. Not just for taste reasons - nearly pure RO would be a bit corrosive.

So forgive my ignorance but if I was starting with distilled, what would someone want to change in the recipe, or would we simply use more of the concentrate (how much?).

Ok so you said maybe do 10ml of the Mg solution, and then I guess I'd do 5 each of the other 2.

sluflyer06 wrote:So forgive my ignorance but if I was starting with distilled, what would someone want to change in the recipe, or would we simply use more of the concentrate (how much?).

Ok so you said maybe do 10ml of the Mg solution, and then I guess I'd do 5 each of the other 2.

Put both the sodium and the potassium bicarb in 100ml in one bottle, and use 5ml of that in 1 liter of pure water (RO, distilled, ZeroWater) for 40 mg/L alkalinity.

Put the Epsom in 100ml in a different bottle, then experiment - try 5ml, 10ml, 15ml to the liter of water which would come out to 19 mg/l, 38 mg/L, and 57 mg/L hardness. Pick the one that tastes best.

Ok sounds easy. thanks

homeburrero wrote:Put both the sodium and the potassium bicarb in 100ml in one bottle, and use 5ml of that in 1 liter of pure water (RO, distilled, ZeroWater) for 40 mg/L alkalinity.

Put the Epsom in 100ml in a different bottle, then experiment - try 5ml, 10ml, 15ml to the liter of water which would come out to 19 mg/l, 38 mg/L, and 57 mg/L hardness. Pick the one that tastes best.

I know I'm going to look dull here, but better than actually *being dull by not asking.

"both the sodium and the potassium bicarb in 100ml in one bottle"

... means 100 ml of solution, or 200 ml of solution?

Yuki

Yuki wrote:"both the sodium and the potassium bicarb in 100ml in one bottle"

... means 100 ml of solution, or 200 ml of solution?

It means only 100 ml of the bicarbonate solution in this particular recipe. The magnesium solution would be in a separate 100ml solution.

To be practical you would probably choose to scale it up to larger than 100ml concentrate containers. Say you had 1 liter containers on hand, you'd just multiply the amounts of each salt added by 10, which is a lot easier to weigh out:

Put 7.5g of the sodium bicarb and 7.5g of potassium bicarb in the same one liter bottle and fill that with distilled.
Then put 10g of Epsom salt in a different liter bottle and fill that with distilled. Shake well, and shake well again right before using either concentrate.

Then when making your brewing water:
Add 5ml of the bicarb concentrate per liter to hit your alkalinity target (of ~ 40 mg/L as CaCO3.)

Experiment with the Epsom salt concentrate, try 5ml, 10ml, 15ml, 20ml, 25ml to each liter of tank water to get you a total hardness of 19 mg/L, 38 mg/L, 57 mg/L, 76 mg/L, 95mg/L. In an espresso machine, unless you see a real taste improvement stick with lower amounts of Epsom salt (to avoid the sulfate issue.)

homeburrero wrote:
Experiment with the Epsom salt concentrate, try 5ml, 10ml, 15ml, 20ml, 25ml to each liter of tank water to get you a total hardness of 19 mg/L, 38 mg/L, 57 mg/L, 76 mg/L, 95mg/L. In an espresso machine, unless you see a real taste improvement stick with lower amounts of Epsom salt (to avoid the sulfate issue.)

Fantastic. It sounds like something I can handle.

Can you tell me what the sulfate levels would be for 5, 10, etc? There's no scaling because we're using potassium, right? It only becomes a sulfate issue now? Or am I confused?

You're wonderful.

Yuki

Yuki wrote:Can you tell me what the sulfate levels would be for 5, 10, etc?

For every 5ml you'd get an 18 mg/L bump in sulfate ion, so it would be 18, 36, 54, 72, 90

LaMarzocco recommends sulfate less than 50 mg/L.*

In general, if you are getting all of your hardness from magnesium sulfate, for every 1.0 mg/L as CaCO3 of hardness you'll have 0.96 mg/L of SO4-- ion.


* The current online spec says "25-50" which is confusing. I once emailed their water team about that and they replied that "Figures of sulfates and silica are just the maximum acceptable data for this kind of minerals."

Yuki wrote:There's no scaling because we're using potassium, right?

No calcium, so there would be no limescale. Probably no deposits at all, even though I suppose there is potential for magnesium carbonate or magnesium oxide deposits at high levels of epsom salts. The potassium bicarbonate certainly wont cause scale.