Airlock Alternative

[fuji6100]

I've done some small lagers in my converted chest freezer (1 gallon, or 2.5 gallon batches) but I want to do a full 5 gallon batch but there is one snag.

With the other 2 corneys and my co2 tank inside (can't leave it outside due to curious cats biting air hoses) the only place I can possibly fit a 5 gallon carboy is on the "shelf" part of the freezer and it just does fit inside WITHOUT AN AIRLOCK. Putting an airlock on it makes it too tall for the lid to close.

So, could I possibly put some sterilized aluminum foil with a rubber band around the top (co2 should seep out) instead? Would this be sufficient during the lagering phase when co2 production is almost zero? Would air begin to diffuse in once co2 production stopped?

Any other suggestions?

[Stodbrew]

Funny, I was thinking aluminum foil all the way up to the point you mentioned it. I would sanitize some foil and put it on, and I think that would work just fine.

[danno]

what about a blowoff tube? I have the same issue, and just run a small tube from my stopper to a quart jar of water...

[ray m]

My only concern about the blow-off tube is however much clearance Fuji has left. That would be better than the aluminum foil, but if there's no clearance left, then the alum. foil would work.:)

[fuji6100]

ok, thanks for the reassurance guys, I just wanted to make sure I wasn't too far off base.