Yeast starter step up : Flask size

[jtbrewcrafter]

Getting ready to brew a somewhat bigger than normal beer, a Winter Warmer. Its going to be about 8.4-8.5% abv and is starting with an orig grav of 1.080. Brewers Friend and Yeastcalc both say I need 402 billion cells. They also say that I can do this with my stirplate doing a 1L starter, decanting, and stepping up to a 1.5L starter. Ive not done a step up starter before and imagine this will take a week or so to pull off.

My question is this. How much room in my flask will my first starter take up once I decant? Do you think I'll be able to decant and then do a 1.5L starter in my 2L flask? Will I have ample space or should I look into buying a 5L flask?

Thanks,
Jon

 

[Pappers_]

FWIW, my starters never have krausen, just a little foam from the swirling. So I would think 1.5 L in a 2 L container would work.

 

[bruteforce]

Ditto. I did 3 rounds of 1.5s in a 2L flask last week and no issues at all. WLP380 (I think, it was Hefe IV), US 05 (because I could) and Wyeast 1968

 

[chickypad]

I regularly do 1.75-1.8 L starters in my 2L flask and they do fine. Except the time the stir bar got thrown, that was a big mess.

 

[jtbrewcrafter]

Awesome. Thanks for the info. Sounds like I'll be just fine. Hope to get started tonight.

 

[rekoob]

No problems.

 

[bbrim]

I always have krausen on my starters and it occasionally foams out. It's never hurt the yeast though. It happens if I go over 1.5L in my 2L flask and use the stir plate.

 

[MaxStout]

I've pushed it to 1.8L in a 2L flask a few times. Never a problem. There might be a lot of krausen, but I've never had it blow out the foam plug. If you're concerned, 1 drop of Fermcap will keep things under control.

 

[CA_Mouse]

I regularly make a full 2 liter starter in my 2 liter flask. I use FermCapS to ensure that I don't get any foaming. Usually the most that happens is a little foam gets into the airlock.

 

[Komocabo]

Same as the above. 2L starters in 2L flask. A few drops of Fermcap and you'll be golden. I use Fermcap AT cuz my local shop has that. Both work

 

[Btaz]

Are you boiling in the flask too? Seems that with fermcap added I can only do about 1.5L without a boil over on the stove

 

[Komocabo]

Nope. Boil in a pot. Chill in ice bath then pour it in sanitized flask using a sanitized funnel.

I never liked the idea of taking glass from boiling directly to an ice bath. I know it's supposedly ok, but just gives me the shivers. Plus I can make a 2L starter without a boil over

 

[chickypad]

I boil 1.8L in the flask with a drop of fermcap. I still watch it pretty close at first boil.