Beginner question - airlock not bubbling

[Alexcbrew]

Hello,

I am new to homebrewing, using a 4.5L brewstore (4.5L / 1 gallon small batch beer brew starter packs) to brew my second batch, which is a chocolate stout. I have a question that I hope more experienced brewers may be able to answer.

Once I put the wort into the fermenter, the airlock started bubbling immediately. I took this to be a good sign that fermentation had started. However after about 1 day, the airlock stopped bubbling. I assume this is too quick for fermentation to have completed, and when I push down on the top of the fermenter, the airlock bubbles again. I've been repeating this process several times a day when I leave/get back from work; depressing the top of the fermenter, causing bubbling. When I get back from work the fermenter is often visibly bulging from the pressure, but there are still no bubbles arising from the airlock.

I've just taken a gravity reading after 12 days, and the beer has almost reached its final gravity, so I think fermentation has still been progressing. I checked the airlock and there was no visible blockage etc.

Has anybody else experienced this? Could carbon dioxide be building up within the fermenter, and how might this affect the beer?

Thanks in advance

Alex

 

[AnimatedGIF]

Hi! I hope you're enjoying your first steps in brewing!
In short, air lock activity is not a good proxy for rate of fermentation. You've done the right thing taking a gravity reading. If two readings 48 hours apart are the same, you're good to bottle/keg etc.

 

[BenBroadley88]

If your lid has bulged again after you've pressed out excess gas, then that's a sign that CO2 is probably still being produced. Plastic buckets are well known to have terrible seals so its highly likely that the gas is escaping through the lid seal rather than fighting against the liquid in the air lock.

As the poster above has already mentioned, take a few hydrometer readings and wait for it to remain stable for a couple of days and your good to go.

 

[Alexcbrew]

Thanks both

 

[Budgie]

I gave up using air locks altogether for that reason. I just stick a solid lid on, but only snap it on about half way round. I always found it far too tempting to think something was wrong when the airlock stopped.