The Reason Why You Should Use A Blow Off Tube

A lot of homebrewers look to get the edge on homebrewing with a few tricks that make life that much easier.  One is a blow off tube if you are fermenting in a carboy.  One thing I should state before I dive deep into the blow off tube is, it’s easier to get the tubing for a blow off tube if you are using a glass carboy verses a plastic carboy.   But with that said, if you can get a tube that will fit a plastic carboy then go for it.

For those who don’t know what the heck a blowoff system is, it is essentially a long wide tube attached to the fermenter that allows the foam from the fermenter to go out of the fermenter and into a bucket of water (or sanitizer – even better).  We normally have in stock  “blowoff tubing”, which is 1 inch inner diameter tubing that fits right into the neck of a glass carboy.  There are a couple of reasons to use a blowoff tube.

First, some people claim a better tasting beer. The theory is that bitter, astringent compounds go to the top of a fermentation and get expelled from the fermenter when using a 5 gallon carboy equipped with a blowoff tube.  I can say from my experience, I have not found that to be necessarily true but hey, I might not have the refined palate that some brewers have.

Another reason is convenience.  Some beers tend to foam up more than others. Wheat beers and stouts seem to be the main culprits and the fermentations can be so volcanic (especially in warm weather) that a 6.5 gallon carboy is not enough space to contain the foam. In fact, the 7.9 gallon plastic bucket can even be exceeded!  A blowoff tube in this case is used instead of an airlock in order to prevent the airlock from becoming clogged up.  Here we come up to personal preference. Since the quality of the beer is not at stake, the method used should simply be whatever works best for the individual brewer.

 Personally, I don’t use a blowoff tube.  I ferment in a bathtub and if the beer foams excessively, well it’s in the bath tub so it doesn’t matter too much to me.  But having a bathtub where I can do that is a luxury and I’m aware of that other people might not have.  If that’s the case then you probably want to think about a blow off tube.  Hope it helps.