Two Lagers At Once, Different Og's

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Hey all,

Just wondering if anyone has had experience here, but I intend to ferment two lagers out at about 9-10 degrees C with Wyeast 2124 (Bohemian Lager), one being a Schwarzbier at 1047SG and the other being a Bock at about 1068SG. I used to knock out two lagers at a time to justify putting my brew fridge out of action for 6-8 weeks, but have generally always done this with similar SG lagers. I generally out of practice raise for a diacetyl rest every time, and am curious about when to start the Bock before the Schwarzbier to near finish together so I can hit the D rest at the same time.

I will use a whole smackpack for each brew, and step the Bock starter up to 2 litres, then decant and restart with 1 litre and dump in at krausen, and the Schwarzbier with a 1L starter and dump in at high krausen.
I am thinking starting the Bock two days prior, does this sound alright?

Also, thoughts here; what temp do u think is best to get the yeast to prior to dumping a 1L starter to a 10degree batch of wort (haven't done a lager for a while)? Should I just let the starter ferment out, chill to 10, decant and dump yeast in, or just start it at say 14C and dump all in at high activity 12-18 hours thereafter? The Bock 2L starter I intend to grow at room temp.

Sorry for the long post. Is 2 days gap okay?

I would be looking to get healthy yeast growth above all else. Can you get a bigger starter going, say 4L ferment out, chill, pour off top, then pitch yeast.

Considering a 4wk ish lager ferment time, I would just pitch at the same time personally.

Two tasty beers those ones!
Hey mate, thanks for that. I only have 2L starter vessels, that's why I thought I'll jsut use a whiole smackpack for each so I get healthy yeast. The thing is though, I have found when making Marzen and Pilsners in the past that the fermentation time has never exceeded 2 weeks, usually its done in 10-12 days at 10-11C, and that's spilitting a Bav Lager pack, stepping up a starter to 2L, chill, decant, new 1L starter and dump at high krausen.

Should I just do a 2L starter and decant it twice, cause I can't do a 4L starter.
personally i would do a bigger starter and pitch the small beer and then use that cake on the bigger one. i know you dont want to tie your fridge up that long but to get enough yeast for a 1068 beer with one yeast pack will need a six litre starter and 2.7l for the smaller beer assuming a very fresh yeast pack.( using mr malty) other option is a two litre for the small beer and a 1.5 litre for the big beer with 3 packs of yeast. if fermenting at the same time i would just start both together and raise for the d rest when the first one is ready as jumping up after the ferment is mostly done wont create any unwanted flavours and might even accelerate the cleaning up in the big beer and possibly give a slightly better attenuation as well.
Yeah its funny how that Mr Malty thing works, cause by that you'll need so much yeast its ridiculous. I personally have fermented lagers with less yeast than old Malty asks for and had great results, maybe its just an 'ideally, you need this much' thing to ensure no stuck ferments, or just to make sure I guess. I'll try and make a decent amount of yeast which is not difficult, but I like both your comments about starting them together and raising together, which should prob give better attenuation of the big beer, I think they are def viable and will most likely do this.

Thanks for the advice guys, appreciate it!

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