Unexpected fermentation

Hi All,  I’m a relatively new brewer, and I am having what seems to me like a strange fermentation.  This was my 2nd all-grain batch (1 Gal) Liberty Cream Ale kit from Midwest Brewing:

Yeast- Munton’s Active Brewing Yeast, 6 gr.;
Hops- U.S. Fuggle 0.25 Oz;
Grains- 1.5 Lbs. Breiss 2-row, 0.25 Lbs. flaked corn, and 0.25 Breiss caramel 10° L.

Brew day was 12/12/2015.

The mash was done for 60 min. at 151-152° F.  Sparge water was 165° F. I aerated by pouring the cooled wort back and forth from brew kettle to fermenter 4 times (which is my usual method, and has provided good results in the past). I pitched the entire yeast packet (dry) when wort was cooled to 70° F.  The fermenter (plastic bucket) was stored at 63-64° F. It began a slow fermentation about 4 hours later, but it soon stopped altogether (by the next morning).  For a week there was no activity, despite some gentle rousing.  I bought another packet of the same yeast and pitched it, and roused it more vigorously.  After some initial intense bubbling (from the rousing), it stopped again and there was no activity at all, until 12/24/2015 when it finally started bubbling through the lock, and continues today.

Anyone have any ideas about what is going on?  I want to do another all-grain kit, but I want to know if I need to change something about my procedures.

Thanks.

It could have just warmed up. When beer warms co2 comes out of suspension.

I think you should measure the specific gravity with a hydrometer. If the gravity is decreasing over multiple reads over multiple days, it is fermenting.

First off, bucket lids don’t always get a good seal, so the airlock activity you’ve seen could be reduced because of that. Have you checked for FG yet? Because the airlock activity you see now may just be CO2 coming out of solution. You know you’re at FG when you get the same reading 2-3 times, a couple days apart each.

Thanks, I’ll check the gravity and keep an eye on it.  I have a Thermostar with the sensor taped to the outside of the bucket, set to 64° F with a 1 degree margin of error and a small heater connected to it.  The temp stays very consistent between 63 and 64° F.  There could be gas escaping from the lid, but I have checked it and it seems tight.  I haven’t had this issue with extract kits, which made me wonder about my mashing and sparging procedures.

6 grams of yeast in one gallon of wort is a lot, I use that amount in three gallons. Your fermentation could have finished pretty quickly. A gravity reading will tell you for sure.

Yeah, I too wouldn’t be surprised if the beer fermented out quickly as well. 1 gallon is not much and a big pitch could easily rip through that.