I need help - water volume calculations

The Homebrew Forum

Help Support The Homebrew Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Michael Burnley

Regular.
Joined
Aug 16, 2014
Messages
220
Reaction score
158
Location
Burnley ..... usually wet !!
I've been all grain brewing for a few years now, and slowly I am getting my head around it and brewing some decent beer - however I am struggling to understand how water volumes are calculated and pretty much all my brew days at the moment are keeping my fingers crossed that I hit my target volume into the fermenter.

There seems to be so many things (that I don't understand) to factor into this e.g grain absorption, deadspace, post boil volume, losses to trub and chiller etc etc ...

Also what puzzles me is how is strike water volume calculated ?

I want to end up with 20 litres into the fermenter and I do a 2 step, 20 mins each batch sparge as well.

Is there a simple way of working volumes out ? I don't mind a bit of variation but I did a guinness clone yesterday and I ended up with 2 1/2 litres too much wort, this made me miss my FG by 4 points. I use Beersmith software, which I suppose helps, but I don't feel happy that I don't know how it has got to those water volume figures.

Thank you
 
Are you using brewing software? I would recommend BrewFather because it is free and excellent. It calculates water volumes for you but the following article may also be helpful:

https://byo.com/article/calculating-water-usage-advanced-brewing/
A lot of these volumes you will have to calculate yourself. It is worth finding an estimate using online tools and then dialling it in to your specific set up.

EDIT - sorry, I’ve re-read your post and seen you use BeerSmith. It will guesstimate figures for you, but you need to check these are correct. For example, measure exactly how much boil-off or loss to trub you get using your system each time you brew and alter the figures in BeerSmith. This will get you closer and closer to the figures for your system. IIRC there is a guide on how to do this on BeerSmith itself.
 
Last edited:
@ceborame @Session Sorry to jump in on this thread but I asked a similar question elsewhere and did not really get an answer so following with interest. I have been looking at the Grainfather community tools but not really seeing how I can adapt for different kit yet.
 
@ceborame @Session Sorry to jump in on this thread but I asked a similar question elsewhere and did not really get an answer so following with interest. I have been looking at the Grainfather community tools but not really seeing how I can adapt for different kit yet.
Do you use BeerSmith as well or the GrainFather software? If you use the GF software it should be fairly straightforward, but I found I needed to alter my grain absorption rate slightly to get the numbers I was expecting.
 
Do you use BeerSmith as well or the GrainFather software? If you use the GF software it should be fairly straightforward, but I found I needed to alter my grain absorption rate slightly to get the numbers I was expecting.
Well, I haven't 'used' either as I am new to brewing but I have started working my way round GF (on PC not the android app) I did register with BeerSmith but as its a subscription model I don't think I am ready for a paid service yet.
 
I always use the desktop version of brewers friend to calculate water volumes. While it only gives one sparge volume, I have in the past simply halved the amount for 2 sparges.
 
I can see there are "Batch Size" and "Boil Length" settings in BrewersFriend v1.41

Batch size is the volume you'd like to end up in your fermenter, I think that's what you refer to. You will start with more water, some is absorbed by grain, some boiled off, some lost inside equipment and pipes (deadspace). What's left goes in your fermenter. So knowing what you want to end up with is a starting point to work back to how much water to mash and sparge with.
 
I use Beer Engine (free software), water volumes from this are always spot on for me. You simply enter the total end volume required and you get simple total liquor and strike liquor volumes calculated based on your grain quantity.
Mash density by default is 2.5 litres/kg, but can be altered easily if required.
You can play around with all sorts of values in the settings, but apart from the mash density, I use the defaults and always get very accurate results.
 
Last edited:

Latest posts

Back
Top