Brewers Friend Dllution Calculator Accurate?

General Homebrew Discussion
1

So I’m brewing an 8.5 gallon batch meant for refilling my 8 gallon whiskey barrel. I don’t think I have the time to brew back to back 4.5 gallonish’ batches (my system can’t handle a batch this big with my desired 1.075 OG). I therefore am thinking of brewing a really big 5 gallon batch and diluting it down to the desired OG. Does anyone have experience using Brewers friend dilution calculator? I definitely have had a number of hit and miss results with online brewing calcs and am curious the accuracy of this one. It says I can dilute a 1.12 gravity / 5.25 gallon batch down to 1.075 with a little over 3 gallons of water. Does that seem reasonable? I most fear over diluting it and way undershooting the OG.

Thanks dudes, you never fail me.

Jason

2

No experience with that calculator, but algebra is telling me you need to add 3.15 gallons of water.

3

Confirmed with algebra. Second source means you can run the story!

EDIT:  V₁G₁ = V₂G₂ is always your friend when calculating volumes or gravity:

(5.25*120)/75 = 8.4
8.4-5.25 = 3.15

Viola!

4

Seems legit. 3.15 pounds of water it is…I mean liters…I mean gallons.

5

Fantastic! Was about to ask a question about dilution and the V₁G₁ = V₂G₂ equation certainly does the trick! Thanks I’ll be attempting a “light beer” and figured dilution was the best way.