Air lock question

[Beer Snob]

I have an air lock on the 1/2 Gal growler that has my yeast starter in it. Its one of those two piece air locks with a little cup sitting upside down within another cup. It was half filled with water but I noticed that the level of water went down. I added a little more water but it went down again. Whats up with that....?

 

[homebrewer_99]

One of two things...it's either evaporation (that's a slow process) or there was a temperature difference (fast process).

Real quick physics lesson here (one I'm sure you already know)...If you move your growler from a warm area and place it in a colder area the inside pressure will "draw" (the water from the airlock) from the outside (the weakest point or opening) until the inside and outside pressures of both reservoirs are even.

 

[mpetty]

An easy way to combat this problem, if you must move your fermenter to a colder area, or cool your wort in your fermenter, is to put vodka in the airlock. If any does drip down into the wort, it will be sterile.

 

[Kaiser]

An even simpler solution: don't use airlocks on your starters. Tinfoil is better since it lets your starter breate. And its easier sterilized; just hold it over a flame for a moment.

 

[Beermaker]

put a balloon on the top and monitor the expansion. Fool proof.

 

[Beer Snob]

It stopped after about 30 or so minutes. I just added a little more water in the lock and the level kept to about mid range.

 

[Beer Snob]

It stopped after about 30 or so minutes. I just added a little more water in the lock and the level kept to about mid range.

 

[Danimal]

I am currently fermenting my second brew and have had the same problem with both of them. It sounds as though you attribute this to a decrease in temperature, but this has happened to me twice now when the temperature increased. In both cases, it was the day or so after I first cooled the wort and put it in the fermenter. I saw that someone recommended vodka for sterilization purposes. I have been using everclear in my airlocks. Can the everclear that has been sucked into the fermenter damage the beer?

 

[Kaiser]

I saw this happening too. When I rocked the carboy and splashed the wort around, and air seemed to be sucked into the carboy. First I thougt it is the temperature change of the air above the wort. But the wort was wamer than the room.

My second guess is, that some of the gas goes into solution and the pressure is reduced.

Kai