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Overdosed Gypsum?

In a moment of stupidity last week, I added 1 tsp/gal of gypsum to both my mash and sparge water. The rest of the brewing process went swimmingly and I currently have a very vigorous fermentation.

I am worried I overdosed the gypsum to levels that may make the beer unsafe to drink. Palmer mentions that high levels of sulfate can lead to diarrhea. Has any one experienced this?

Well someone gave me some mushrooms he picked and told me I wouldn’t get sick but I may have diarrhea for a couple days. So no you won’t get sick but you may have diarrhea for a couple days.


That would seem to be alot… 5 gallon brew? Sneezles61

I believe it’s 4 grams per tsp…

For reference: My latest 10 gallon batch used 3.8 grams in the mash, and 4.1 in the sparge. This is for a very pale hoppy lager with relatively soft water to begin with.

Yes, well 5.25. Doing some rough math I believe it comes out to around 900 ppm.

900ppm?!..technically speaking…that’s a shite ton of sulfates…not sure I’d drink it…depending on the yeast you used your finished beer pH could be very acidic.

Most I’ve ever gone is about 300ppm on an IPA to try and accentuate the bitterness…have since dialed that target back to low 200s…

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Where did you get the pH reading from? Mash? Kettle? pH meter or test strip?

That’s not terribly low if it’s a valid kettle reading.

I think he meant 5.25 gallons.


ah yea gotcha unc…helps to read back huh

Ran the numbers through bru n water, which is showing 590 ppm. An extreme number to be sure, but under the worrysome mark of 750. People seem to treat bru n water a reliable. Thought?

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Brunwater is reliable and I’m going to edit this post to reflect the fact that @dccabbage is correct.

I input 20g of gypsum in the brunwater field where I should have entered 4g/gal. So I was way off.

That’s still a shite ton of gypsum.

This is the piece of the puzzle I have yet to understand… I keep going around it or avoid it all together…
Perhaps I’m reading it all wrong… “to the mash AND the boil”? 2 different additions? I hope DC weighs in to set me straight… Sneezles61

Some brewers treat their sparge with the same additions as their strike water. When I first started adjusting my brewing water I did the same thing but now I only adjust my sparge for pH with lactic acid. The only other elements I’m usually concerned with are the sulfates, In IPAs. and the calcium level which can help with finished beer clarity. Both are present in sufficient amounts in my well water that I don’t need to add more in the sparge.

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I don’t really do much additives except for pH in the mash… But sometimes I get that wild hair thingy going… Next time I do some taping around the house… I’ll mix in my gypsum baggy… That’ll fix things… right? Sneezles61

Guys please note that I edited my post above regarding the bruanwater calculations for gypsum ppm. Garbage in garbage out right?


Does DC get an Atta brewer? Should be a badge for that!
:unicorn: thereOh geez, is that… A unicorn? Crap… thought it was a fist with a sword… Those gizmos need to be larger… Or I need a bigger screen… Sneezles61

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