Up until now I have been using a 61/2 gallon bucket as a primary but I also own a 6 gallon glass carboy that i want to use as a primary for my next batch. Question is should I use a blow off or does everyone think I have enough head room to just throw a airlock on? at this point I only brew ales and I realize different beers ferment more " actively" but in general should I ok with just the airlock. Thanks.