Reducing SG, what amount of water?

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Mikeyd

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Hi all,

Got a brew on last night, my Sg ended up at 1.060 which was a little higher than I wanted.
Is there a chart or way of working out how much water I would need to add in order to reduce the Sg? I’m sure there is some way but I couldn’t find anything.
I can’t use my hydrometer as I would normally as I had to add the yeast last night unfortunately.

Thanks.
 
Be careful with dilution, you do not want to over do it, you may dilute the SG but you dilute everything else hops bitterness.. unless of course you miss your water numbers then you should be not too affected by it.
 
Ah excellent I’ll have a look. Thanks.

Yeah that’s true, don’t want to dilute it too much!
Would the best way to deal with this in future brews is to add an extra litre or two at the mash stage?
 
Ah excellent I’ll have a look. Thanks.

Yeah that’s true, don’t want to dilute it too much!
Would the best way to deal with this in future brews is to add an extra litre or two at the mash stage?
After 7 or 8 AG's in still trying to pin down an exact total in/total put formula. I'm getting close. For me it's been a matter of 1)ditching batch sparging cos it just doesn't work for me. 2) moving to batch sparging and keeping precise volume notes and fine tuning from there each time.
 
I wouldn't advise adding water after fermentation has started. I've tasted beer that has been diluted and it tasted just like that, diluted beer. The time to start looking at your gravity is prior to boil, together with the volume in the boil, that way you adjust your boil accordingly or add water at that stage. How much did you overshoot your desired OG by? A few points shouldn't make too much difference. I overshot my first AG by quite a few points and ended up with a few litres less of a beer that was over 1% higher in ABV than the recipe. Still tasted nice though!
 
I wouldn't advise adding water after fermentation has started. I've tasted beer that has been diluted and it tasted just like that, diluted beer. The time to start looking at your gravity is prior to boil, together with the volume in the boil, that way you adjust your boil accordingly or add water at that stage. How much did you overshoot your desired OG by? A few points shouldn't make too much difference. I overshot my first AG by quite a few points and ended up with a few litres less of a beer that was over 1% higher in ABV than the recipe. Still tasted nice though!

Ah ok, so take a hydrometer reading pre boil (temp adjust) then decide if it’s going to need a top up? Although doesn’t it become more concentrated after the boil so surely this still won’t give you a final Sg? Or am I missing something?! Sorry newbie questions!
 
Yes it does become more concentrated, the longer you boil for the more concentrated it will become. You need to know your boil off rate as well as how much is left in your boiler after transferring the wort to the fermenter. Boil off rates will vary from setup to setup, it takes a bit of trial and error to find your individual figures. Have a look at the website howtobrew.com it is very good.
 
It's a straightforward formula, which can be used for both dilution and concentration:

Volume a x Gravity points a = Volume b x Gravity points b

You can then transpose this for your purposes. For example, if you have 20L of 1.060 wort that you want to dilute to 1.050 then...

Volume b = (20 x 60)/50 = 24

Meaning you need to add 4L.

Or if your pre-boil gravity is 1.045 at 28L and you want to know what it'll be after boiling off 3L then...

Gravity b = (28x45)/25 = 50.4

Meaning a post-boil gravity of 1.050.

Or of course you could just use the calculator, but personally I like to know how to do these things the old fashioned way :D
 
Thanks for the replies. Next time I’ll make sure I measure Sg pre boil and also work out my boil off rates.
 
Sorry to hijack this thread but my problem is the opposite in that i ended up with 28lt instead of 26lt. could my boil off rate be incorrect and how do i work out the approx ABV. I started off with a OG of 1.039
 

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