# About to do first AG but have one question....

### Help Support Homebrew Talk:

#### fat x nub

##### Well-Known Member
So i am doing a 5 gallon batch of Centinneal Blonde and it says the boil size is 6.6 gallons i think. Can somebody tell me what i do water wise...like how much i add and then what happens to the other 1.6 gallons after i boil??? I am a bit confused . Please help

#### z987k

##### Well-Known Member
You should collect 6.6 gallons pre-boil and then over the course of the 60minute boit, you will boil down to 5 gallons.

OP

#### fat x nub

##### Well-Known Member
aight thanks a lot...i guess it evaporates or somethin

#### Bobby_M

##### Vendor and Brewer
Typical evaporation is 1-1.5 gallons per hour of boil time. If you get less, you're not boiling hard enough.

OP

#### fat x nub

##### Well-Known Member
Typical evaporation is 1-1.5 gallons per hour of boil time. If you get less, you're not boiling hard enough.

aight thanks...and dont i loose water during the mash due to grain absorbtion?

#### BigKahuna

##### Senior Member
i guess it evaporates or somethin
I think It's the Somethin...

and dont i loose water during the mash due to grain absorbtion?
Your grain will absorb roughly 1/10 of a gallon per pound of grain. So if you have a 10# grain bill, and you mash with 2.5 gallons of water, you can drain 1.5 gallons off then you'll need to add your sparge water before you get any more.

#### RichBrewer

##### Well-Known Member
Post your grain bill and we can give you a better idea of how much water you will need. Most folks use 1 1/4 to 1 1/2 quart of water per pound of grain for the mash and 1/2 gallon of water per pound of grain for sparging.

OP

#### fat x nub

##### Well-Known Member
Post your grain bill and we can give you a better idea of how much water you will need. Most folks use 1 1/4 to 1 1/2 quart of water per pound of grain for the mash and 1/2 gallon of water per pound of grain for sparging.
its 8.75 lbs of grain

#### jay075j

##### Well-Known Member
You may also want to consider using some form of brewing software (beersmith, promash).

#### sirsloop

##### Well-Known Member
You may also want to consider using some form of brewing software (beersmith, promash).
x2

Beersmith is shockingly accurate once you get your efficiency numbers dialed in!!