check valve or blow off tube?

[Brewslikeaking]

The check valve we put sanitizer in and stick in the top of our carboys and buckets. Or a blow off tube for initial fermentation first?
Can you please explain the need for each or for one over another? Is it blow off tube for initial fermentation then a check valve once fermentation has slowed. Is there any need to put on a check valve? Can you simply leave on the blow off tube for the entire duration?

 

[eddiewould]

What you're referring to as a check valve us actually called an airlock.

Normally you'd use a blowoff tube to start with and then possibly, switch to a airlock once fermentation dies down. I personally don't bother with airlock.

Check valve is used with kegging to stop beer going into the gas lines (protects the regulator).

 

[Brewslikeaking]

So there's no necessity for the airlock? I'm just wondering about space in my fermentation freezer, I can fit a bigger carboy in but not with the airlock. So basically a blow off tube for a number of weeks has the same effect as an airlock?

 

[Toga]

A blow off tube stuck in a jar full of sanitizer works just as well as an air lock. This thread did get me thinking though. It may not be a bad idea to to add an actual check valve (not a airlock) to your blow off tube.... it would keep from sucking water back in while cold crashing I may have to experiment with this

 

[Ski12568]

Or sanitize a piece of aluminum foil and cover the top of the carboy. You'll still get a mess if your yeast go nuts.

 

[MyBrauHaus]

Both airlock (the thing you stick in the top) and blowoff (with the tube) have their uses. I prefer airlock because they're smaller and easier to clean (generally). The tubing on the blowoff can be harder to clean because the trub can dry inside it which means you need to soak it in some oxyclean or other cleaner to prevent future infection. A blowoff is an absolute necessity on some beers even if you think you have plenty of room in the fermenter - you'll learn pretty quickly when to use one vs. the other.

Personally, I use an airlock unless I know I need a blowoff, but that's personal preference and I've been surprised a couple of times with a really robust fermentation that caused me to scrambe and replace the airlock with a blowoff.

 

[kh54s10]

I start EVERY fermentation with a blow off tube. I use Better Bottles that are only 6 gallon so I have a little less head space than a glass carboy (6.5 gal) Buckets have more headspace but if the airlock clogs it can blow the lid and you could be cleaning krausen off the ceiling. Save yourself the clean-up, start with the blow off. Unless I need the blow off tube for a new batch, I leave it for the entire fermentation.