Slow fermentation onset, then blowoff, then stuck fermentation

I'd like to think I take pretty good care of my fermenting beer. Always make a starter using Mr. Malty, oxygenate with a William's oxygenation kit, ferment in a mini fridge with the temp sensor against the glass of the carboy.

Even with all of that, my beers take upwards of a week to get to high-krausen! Any ideas why this is happening?

I wait for the beer to get to fermentation temp before pitching. I had thought that giving the beer the royal treatment as I do would speed up the fermentation process, but instead it seems as though it's made the beer take longer.


In a recent case, I brewed a Dragonmead Final Absolution clone that slowly developed to a case of blowoff (6 days). After the fermentation subsided, I moved it outside the fermentation chamber and let it sit for 3 weeks before transferring to a keg to further condition. I took a sample from the siphon after the beer was done transferring and found my gravity was 1.046! Could this be because the sample was from the bottom of the carboy?

I've recently started taking gravity samples from the siphon after the transfer is complete, and am wondering if that giving me an artificially high measurement.

I have read that the O2 kit actually delays the onset of fermentation because the amount of oxygen present in the wort upon pitching is so great that the yeast produces new cells for a long time before starting the actual fermentation process. Forgive me for not knowing specifics, but I have found it true in practice. I use the O2 wand and my fermentation is faster, but start later, usually 3-4 days after pitch. I have never had a blowoff and always get to FG within the week.

How much headspace do you have in your fermenter? Is there a lot of sediment in your sample? Have you let the sample sit with the hydrometer in it for 10-15 minutes to see if it settles?

That is very interesting about the yeast and oxygen!

I make 5.25 gallon batches in 6.5 gallon carboys, so there is usually plenty of headspace. As far as sediment and the hydrometer, I have one of those Brix meters with an ATC gravity feature that only needs a few drops for a reading, so I can't comment on the consistency of the sample, just that it is often the very last bit of liquid before the siphon kicks.