Big Mouth Bubbler Fermenters

[BugAC]

I was recently gifted a couple of 5 gallon glass big mouth fermenters. I've always used the standard glass and sometimes PET carboys. Do these things have an issue with oxygenation? The lids that came with these are not screw on, they are push in with a rubber gasket that creates a seal. However, one of them, the gasket is more worn so when i press the lid down, it slowly rises up. I'm pretty stringent on preventing O2 ingress in my beers, and the design of this fermenter feels like that is it's biggest problem. In addition, i do o2 free transfers to my kegs with a steel racking cane that goes through a carboy cap, and that doesn't appear to work with these fermenters.

 

[mac_1103]

Do these things have an issue with oxygenation? The lids that came with these are not screw on, they are push in with a rubber gasket that creates a seal. However, one of them, the gasket is more worn so when i press the lid down, it slowly rises up.

I've never used one but FWIW you can get replacement lids here for example. They come with either one or two ports that take #6.5 stoppers. I think they're silicone which is not great for oxygen permeability.

 

[Indian_villager]

I was recently gifted a couple of 5 gallon glass big mouth fermenters. I've always used the standard glass and sometimes PET carboys. Do these things have an issue with oxygenation? The lids that came with these are not screw on, they are push in with a rubber gasket that creates a seal. However, one of them, the gasket is more worn so when i press the lid down, it slowly rises up. I'm pretty stringent on preventing O2 ingress in my beers, and the design of this fermenter feels like that is it's biggest problem. In addition, i do o2 free transfers to my kegs with a steel racking cane that goes through a carboy cap, and that doesn't appear to work with these fermenters.

Lol, if you go back 10 years or so on these forums you will find heaps of reports of the same issue. I still have 2 of the plastic ones that I use to this day. The easiest way to fix this is to flip the gasket upside down so that the wide part is toward the fermenter and the skinny part is toward the top of the lid. This will hold it nice and secure.

 

[day_trippr]

A cautionary note...or two...

https://www.homebrewtalk.com/threads/big-mouth-bubblers-are-dangerously-thin.486222/

 

[Maylar]

The lid can be held down with tape.