So I decided to dry hop my Hazed and Infused clone the other day, with 1 oz of liberty and 1 oz of centennial. I had the beer in primary for 5 days, and then secondary for another 5 days before the dry hopping. There were a few bubble coming up through the beer, but no air lock activity while i've been watching. I threw the 2 oz into the 5 gallon secondary fermenter, and gave it a swirl to get everything wet.
Well, it wasn't long before the beer really started bubbling, and then the airlock started bubbling, about 1 bubble per second. As I didn't have much head space, I grew concerned when the foam and hop cone started creeping up and up and up. With more bubbles that didnt seem to be slowing. I said to myself, ah #&$*!, and ran out to the garage to get my blow-off tube if it came to that. I was hoping it would stop rising, but as it neared the lip of my fermenter, I decided to push some of the floating/rising hops back into the fermenter with a sterilized large spoon. That bought me some time, but in another 20-30 minutes I had to do it again. I kept a watchful eye on the whole process for about 2 hours before I was satisfied that it wasn't going to blow over. The bubbling and airlock slowed dramatically, and I finally went to bed.
Update - 30 hrs later, the hops have dropped back into the beer, danger has been everted. All is well. The beer, however, is still bubbling a little bit (more than before i added the dry hops), but no activity in the air lock over the 2 minutes I watched. This doesnt concern me, but, throught the whole process I couldn't figure out why I was getting this reaction/bubbling. It was as if I had added another pound of sugar. Is there some sort of chemical reaction with the hops that I don't know about? Anyone have any insight? Anyways, I am looking forward to the finished product, it should be a good one!