Fastferment conical/Mr Beer seal.

[Syncman]

Only brew 2 gallon. Thinking of the 3g Fastferment, but see that people are posting/complaining about not getting an airtight seal on the lid. Some are building up with silicone and aftermarket washers. Question is, is this an actual problem? The Mr Beer kegs that I have been using up to now, have 4 notches in the threads so gas can escape. No airlock. An airtight seal is NEVER possible. Made some great beer in them, but one "melted" cos wort was too hot, another the lid thread cracked.

 

[BrewZer]

Only brew 2 gallon. Thinking of the 3g Fastferment, but see that people are posting/complaining about not getting an airtight seal on the lid. Some are building up with silicone and aftermarket washers. Question is, is this an actual problem? The Mr Beer kegs that I have been using up to now, have 4 notches in the threads so gas can escape. No airlock. An airtight seal is NEVER possible. Made some great beer in them, but one "melted" cos wort was too hot, another the lid thread cracked.

I've got a HDPE conical with a lid that doesn't come standard with a gasket, and as the manufacturer explained, you only really need an airtight seal if you want bubbles in your airlock.

Carbon dioxide is heavier than air, and as the wort ferments, will displace air above it as it fills your fermenter up to the lid. As long as you don't disturb that layer of CO2, you should be OK.

 

[Jtvann]

Gas particles mix equally. The CO2 blanket is a myth.

 

[CoreyD]

I have a 3g Fastferment and have no problems with it. I did notice that there is very little activity in the air lock, but have not had any issues with o2 getting in. I love it. I had been using a 3g Brewdemon. It works fine, but not as nice as the Fastferment. It's like having a primary, and a secondary, with out transferring.

 

[JohnSand]

I agree that an airtight seal is un-necessary. As long as nothing risky can fall into your wort a lid will be fine.