Brewed an English Brown on Mon night. After pitching the yeast, it took a couple hours longer to get started than my first two batches but by the morning, every thing looked normal with a nice, even layer of kraeusen. I thought it was done, but, by the time I got home from work, it had started up again. It was going so strong that I had to put on a blow-off tube. That was last night @ 26 hours after pitching. It's now Wed morning and it still has a very strong and steady heartbeat 35 hours after pitching.
1. What caused it to stall in the first place?
2. What causes it to be so much stronger and longer that my previous batches? Choice of yeast or something else?