Seems like a hell of a lot of water!


Jun 5, 2013
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Just revving up for the first brew day of 2015 (very slow of the marks this year!). I have entered my recipe (an Oatmeal Pale Ale) into Brewsmith 2.

I am aiming for a final batch size Iinto the fermenter) of 22.70 litres (about 5 gallons in old money).

I have set mash profile to Single Infusion, Medium Body, Batch Sparge.

I have selected Batch Sparge that fill 74% (to get two equal batches)

Beersmith is telling me to Mash In with 14.29 litres then to batch sparge with 3 steps (Drain Mash Tin, 13.5 litres, 13.5 litres)

That's a total of 41.29 litres of water.

Now I know i'll loose some to the mash absorption and some through evaporation during the boil but that still seems like a hell of a lot of water t me.

What do you think?


In your recipe, how much loss do you have set for trub?  What is your boil-off rate and how long are you boiling?  How much grain are you mashing?
Loss to Trub = 4.00 litres
Boil off = 7.00 litres / hour (20.1%/hour) set by Brewsmith
Boil for 1 hour
Mash Grain Weight = 5.48 kg


Just running through the water balance figures:

22.7 litres into fermentor
4 litres for trub loss
7 litres for boil off (quite a high figure, you may be able to reduce your energy consumption)
5.5 litres for grain absorption (assuming a standard mash tun)

total is 39 litres.

I forgot to ask about dead space in your mash tun, but this may be the difference.
I forgot to add that Beersmith tells me that the Est Pre Boil Vol = 34.77 litres.

If the batch size is 22.7 litres that means 12.07 has to be lost due to evaporation + loss to trub.

Is that rather a lot?

I often find that my measure OG is lower than it should be. I assume it's because of adding to much sparge water?

I would recommend working to dial in your process (equipment profile) to reflect your actual results.  It would appear as though your grain absorption, boil off rate and mash efficiency all need to be looked at.  On your next brew, or if you have the measurements from your last brew, record your actual water volume in (both mash and sparge), your collected wort and wort gravity pre-boil, your post boil volume and gravity, and volume to fermentor, volume of trub left over.  From these you can calculate the amout of grain absorption, boil off rate and actual volume losses in your process.  Use these figures to reconfigure your equipment profile (the grain absorption is a universal variable and can be found in your 'options' >> 'advanced' settings).

Once this is done, check your actual mash efficiency versus the projected efficiency from BeerSmith (it will give you actual vs planned numbers on the mash page).  Use this number to reconfigure the Brewhouse efficiency in your equipment profile, adjusting the brewhouse efficiency number to achieve your actual mash efficiency.

Do this for the next couple of brews until the program has the correct settings to reflect your actual results better.