Fermentation and FG? Can anyone tell me a good rule of thumb?
- Thread starter elaeace
- Start date
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The airlock really isn't a good indicator of fermentation. There is alot going on before and after the airlock activity. As for a rule of thumb about taking samples, I usually just forget about it for 2 or 3 weeks and then check to see where it's at. But More then likely it'll be done after three weeks.
Hawkseven
Active Member
I agree 100% with wcrooker, additonally there are so many variables (type of yeast, ferm temps, lid seal) that counting bubbles can be an excercise in futility. Do a search for Revvy's thread on the subject its a good read and will answer you question in depth.
+1
Your airlock is not a hydrometer. You cannot tell anything from an airlock. If it does bubble then yeah you have fermentation. If it doesn't bubble, that doesn't mean you don't have fermentation (I know, double negative). You can have fermentation but not a lot of CO2 being produced. The only way to tell if your fermentation is complete is by taking a gravity reading.
If you pitched the right amount of healthy yeast for your style beer and you have kept a good eye on fermentation temp (the temp of the liquid not the ambient temp) then you should be able to complete most of your ales by 2 weeks. I used to not even touch the beer for 4 weeks but after getting some good advice on here, I have been able to produce great beer in 2 weeks. Keeping it longer won't hurt though.
If you didn't pitch enough yeast or you think the temp control wasn't the best, you might want to leave it in longer so the yeast can clean up a little.
Overall, I would say leave it in for 2 weeks and then check your reading. If it is around your FG then check it two more days in a row. If it doesn't change, it is complete. If you feel like you haven't pitched the right amount of cells or your temp was too high or low, then leave it in for another week or two before checking it.
