How much Mg is too much?

[JerD]

The Mg is a bit out of range. I'm pretty sure it's close enough, but I'd like to make sure.
60% Home water/40% Chicago w/1.2 gram addition Calcium Chloride

Results:
Ca: 91 ppm
Mg: 42 ppm
Na: 48 ppm
Cl: 55 ppm
SO4: 54 ppm
CaCO3: 285 ppm

RA: 195 (21 to 26 SRM)
Cl to SO4: 1.03 (Balanced)


I'm going with it as it is. Vienna is at 68 ppm Mg and Dortmund is at 42ppm. Some decent beers have come from these places, right?

 

[brewingkitty]

um, unrelated to your water profile, but any other situation and too much magnesium is when it bursts into flames.

 

[Shrewd_Alchemist]

That's only pure magnesium metal, and only if you manage to scrape away the oxide coating that forms on it when it hits the air. What's in his water is magnesium ions from salts like phosphates, chlorides, etc.

Sorry OP, I'm not exactly sure how much is too much. What is the range that you have seen?

 

[jeffmeh]

I suspect that if you brew with it you will be fine, but I cannot state that for certain.

If you choose, you could dilute 28% with distilled water to get the Mg down, then add minerals back to get the values you want. You may also want to add some HCl or Lactic acid to get the RA for lighter SRM beers.

I am no expert, but I can work a spreadsheet, lol.

 

[Beerrific]

Palmer (http://www.howtobrew.com) says that Mg in excess of 50ppm will start to lend off flavors. I am not sure if that means in the final beer, I assume so. After concentration from the boil you will be close to 50ppm.

 

[remilard]

Plus there is magnesium in the malt.

I would be more concerned with the alkalinity.

 

[AiredAle]

The other level of "too much magnesium" is when it sends you to the bathroom with the Hershey squirts. Though you'd have to drink a lot of your beer at 50 ppm to get the 2000 mg needed for its laxative effect.

Diluting with RO or soft water then adding minerals as suggested is the way to go to get a better mineral profile. Is Chicago water from a surface water source? If so, it will be fairly soft, and once you removed/neutralized the chlorine/chloramine it would probably be a good base for mineral additions to get the profile you need for the style you're brewing.

I assume you are making all grain beers, and will adjust to fit the style. If you are making extract beers, the mineral profile is less important, as long as you don't have too much of any mineral.

 

[JerD]

This water recipe is for a stout, roughly 24 srm so according to spread sheet, the alkalinity and all else seem to work out. I'm trying to get the best water blends possible with a minimum of dilution and salt additions. No other reason than just being quircky. My home water is often diluted 90% distilled. Even though Ca is 86, Mg is 62, not enough to bring down total alkalinity of 499.