Carboy Size

[msu05]

I just bottled my first batch this weekend. When I bought my brew kit a while back I added a 5 gallon carboy as a secondary fermenter knowing you don't want too much headspace in the secondary. The 2 books I read and the guy I learned how to brew from all recommended a secondary if for nothing else to clear the beer a little more and get it off the trub to avoid off tastes. After learning more about brewing through actually doing it and this site, I've found that the secondary isn't all that necessary. My question is can I use a 5 gallon carboy as a primary fermenter for 5 gallon batches with a blow off tube? I'm assuming the fermentation from a high gravity beer will probably be too much for the blow off tube to handle in a 5 gallon fermenter. The only reason I ask is it would be nice to have 2 batches going at once with the equipment I already have. One in the plastic bucket and another in the carboy.

 

[danielinva]

Assuming you aren't buying kits you could always scale back recipes to 4 gallons, then you'd certainly be fine. Another option would be using some anti-foam in combo with your blow off tube. I would worry about poor attenuation with just using a blow off though. A big blow off in a 5 gallon carboy could end up with you losing a significant amount of your yeast.

Edit: Forgot to mention that you can also mix up some apfelwein in a 5 gallon carboy without even worrying about the blow off.

 

[TipsyDragon]

yes you can ferment 5 gallons of wort in a 5 gallon carboy with a blow off tube. but by the end of fermentation you will probably be left with somewhere between 4 and 4.5 gallons of beer.