Calcium Chloride - adjust for purity?

[Brewer #421288]

I've got some calcium chloride flakes (77% purity, which seems to be around the norm) that i'll be using for water adjustment, but I'm struggling to figure out if the water calculator already takes the purity into account (so if it says 5 grams I should just measure up 5 grams), or if I should adjust how much I use by 1/0.77 to get up to "100%".

 

[Minbari]

It's prolly not that critical. I have always just put in the amount the calc said

 

[Megary]

In the calculator, are you choosing Calcium Chloride (anhydrous) or Calcium Chloride (dihydrate)?

I'm not positive on this, so don't quote me here...but I believe the calculator assumes the anhydrous to be (close to) 100% pure (no water molecules) and the dihydrate to be somewhere between 75-80% pure (CaCl + 2H20). In reality, I bet neither are correct because CaCl is constantly trying to absorb water.

@Pricelessbrewing
@Yooper

 

[Brewer #421288]

Thanks for your quick answers! It seems like your beliefs are correct when comparing the two types. Adding 1 gram to 10 liters, anhydrous adds 36.1mg/L (of Ca+2) while dihydrate adds 27.3mg/L, which is about 75.6% as much.

 

[Minbari]

In the calculator, are you choosing Calcium Chloride (anhydrous) or Calcium Chloride (dihydrate)?

I'm not positive on this, so don't quote me here...but I believe the calculator assumes the anydrous to be (close to) 100% pure (no water molecules) and the dihydrate to be somewhere between 75-80% pure (CaCl + 2H20). In reality, I bet neither are correct because CaCl is constantly trying to absorb water.

@Pricelessbrewing
@Yooper

interesting.. learned something new. I have no idea which I have, but I do keep it in a sealed container. so hopefully is doesnt absorb much water.

 

[Megary]

interesting.. learned something new. I have no idea which I have, but I do keep it in a sealed container. so hopefully is doesnt absorb much water.

I think we homebrewers are safer assuming "anhydrous" so as not to overdose the minerals (even though it's a certainty that we are using something in between both, without any way of knowing exactly how far in between.)

 

[Donoroto]

Anhydrous is a powder while dihydrate are little balls ("crystals"). Anhydrous is less common, especially in brewing.

 

[Megary]

https://www.morebeer.com/products/calcium-chloride.html

Description says it is anhydrous.

 

[Minbari]

Anhydrous is a powder while dihydrate are little balls ("crystals"). Anhydrous is less common, especially in brewing.

mine is definately the balls

 

[BarbarianBrewer]

Well now I'm confused. I read (don't remember where) that homebrewers can be assumed to use dihydrous CaCl because you would be unlikely to find anhydrous CaCl outside of a laboratory due to how difficult it is to keep water out it.

 

[Megary]

Well now I'm confused. I read (don't remember where) that homebrewers can be assumed to use dihydrous CaCl because you would be unlikely to find anhydrous CaCl outside of a laboratory due to how difficult it is to keep water out it.

I just checked my bottle. It’s an LD Carlson special (company motto: we make nothing, but repackage everything!). It doesn’t say one way or the other. We can safely assume it is unlabeled because they have no idea there is even 2 different. *shrug*

I read somewhere (probably Bru’n Water) that homebrewers should assume anhydrous, unless they know otherwise. I believe the reason was as I wrote above, to prevent against adding too much. Though as I understand it, that guarantees that we are likely adding too little since even anhydrous is not 100% pure. A head scratcher, for sure.

 

[BarbarianBrewer]

I read somewhere (probably Bru’n Water) that homebrewers should assume anhydrous, unless they know otherwise. I believe the reason was as I wrote above, to prevent against adding too much.

This thread on the AHA forum backs this up. Thanks @Megary for educating me on this!

 

[Donoroto]

I disagree. Anhydrous CaCl is a lot like Dry Malt Extract: Give it a second, and it'll pull any available moisture from the air, thus becoming dihydrate.
Even the dihydrate will pull moisture from the air, eventually turning into a puddle. Try it.

But, I DO agree that it really doesn't matter much.

 

[BarbarianBrewer]

Even the dihydrate will pull moisture from the air, eventually turning into a puddle. Try it.

I always add CaCl last because I can see the weight climb a few tenths of a gram after it sits for a few minutes.