My airlock isn't bubbling!
by peas_and_corn on 02-19-2009 at 03:56 am

Relax. A bubbling airlock is not a wholly reliable way to determining whether your beer is fermenting. Fermenters are rarely made airtight, and as such the CO2 produced by the fermentation could be escaping some other way. The best way to determine whether your beer is fermenting is the following- 1- Does the beer have 'krausen'? This is a foam that sits on top of the beer as it's fermenting. If there is one there, then congratulations! Your beer is fine. 2- Is your SG falling? If so, then your beer is fermenting and there's nothing to worry about.

The airlock is not particularly necessary for the fermenter - the main purpose is to maintain a barrier against oxygen and any airborne nasties. Many brewers forgo the airlock entirely, and simply use glad-wrap secured over the top of the fermenter with no lid (which has the added advantage of being transparent) or place an upturned (and sanitised) glass or bottle lid over the airlock grommet.

Falling SG
We have OG, SG, FG. Original, Specific and Final Gravity of wort.
Falling SG indicates fermentation is going on (as discussed). If you SG is stable over a 3 day period its likely fermentation has stopped and your ok to bottle. However if your brewing in cooler temps then your yeast may have just gone to sleep. pay attention to your temp ranges and what they should be for the yeast your using.

Pressure
The bloop bloop of your airlock is caused by pressure building up in the fermenter. If you airlock isn't bubbling but you want to make sure somethings going on, you can push down on the top of your fermenter lid and see if the the water level in your airlock moves.

Patience is a Virtue
Ok so you've pitched your yeast and nothing's happening? Settle, relax, have a beer. Yeast can take its time to get going. They have a lot of work to do, especially if you're using dried non-rehydrated yeast (see Yeast Wiki topics on this - http://www.aussiehomebrewer.com/forum/inde...showarticle=20). They have to eat and multiply: usually 24-48hrs and you're in business. Yeast can take shorter or longer to get going. Just wait and see.