My friend and I have our second-ever batch in the primary fermenter, and have witnessed what we think are some unusual circumstances.
First, we brewed a batch of Brown Ale from Charles Papazian's book (don't remember the name he gave it) as follows:
Crushed UK Crystal Malt
Low Initial SG, Weird Fermentation Progress
Moderator: slothrob
Thoughts on your questions:
1) It sounds to me like your bucket lid isn't getting a good seal, which allows gas to escape and not through the airlock. It happens alot.
2) Some yeasts like to flocculate quickly taking them 'out of the game' so to speak. Rousing the yeast to get them back into suspension helps. Take your fermenter and rock it slowly in a circular motion
3) Are you correcting for temperature? Is your hydrometer and/or thermometer calibrated? Check it against distilled water at the reference temperature--it should read 1.000. Some hydrometers are cheap and are off a bit. If you get any other reading than 1.000, remember the difference and adjust future readings by this offset. Check your thermometer against a glass of ice water and boiling water. It should read 32F and 212F (at sea level, adjust for altitude). Let your ice water settle for 5 minutes so the temperature stabilizes. Again, make note of any offsets for future compensation.
Hope this spurs some ideas.
1) It sounds to me like your bucket lid isn't getting a good seal, which allows gas to escape and not through the airlock. It happens alot.
2) Some yeasts like to flocculate quickly taking them 'out of the game' so to speak. Rousing the yeast to get them back into suspension helps. Take your fermenter and rock it slowly in a circular motion
3) Are you correcting for temperature? Is your hydrometer and/or thermometer calibrated? Check it against distilled water at the reference temperature--it should read 1.000. Some hydrometers are cheap and are off a bit. If you get any other reading than 1.000, remember the difference and adjust future readings by this offset. Check your thermometer against a glass of ice water and boiling water. It should read 32F and 212F (at sea level, adjust for altitude). Let your ice water settle for 5 minutes so the temperature stabilizes. Again, make note of any offsets for future compensation.
Hope this spurs some ideas.
CO2 Release
The immediate activity you saw in the airlock is CO2 being released. But just give it some time--it'll do it's thing.
Update...
Over the past 3 days, there has been no change in the SG (still at 1.016). At this point, we have transferred to our secondary vessel with the intent of letting it bulk age for 1-2 weeks. Having come up a bit short on the final SG, is there anything to be done for this batch or is the safest thing to simply accept the result? While I understand that there may be some further fermentation over the next week, I'm not expecting anything dramatic given that the SG has been unchanged for a few days.
Go With It
I'd go with what you have and accept the results. I think there's more that can go wrong if you try and fix it.
That's What I Thought
That's what I thought. Is there any real concern that our yeast will be too tired to carbonate during bottle conditioning?
Should be Fine
I think they'll be fine. If it was a really high gravity ferment and you'd been re-using the yeast for awhile, I might think differently. When I bottled I found it took 2-3 weeks to get consistency across all the bottles.