I always kept them in a root cellar in wooden boxes and old leaves. Never saw them reproduce either. Occasionally I would have entire box die and rot! I never figured out why. Sounds like it could have been a temperature issue or not enough food. IDK.
Sean,
I'm guessing I was about 12 when I let a 2-gallon bucket of night crawlers die and rot in the trunk of my dad's car for a week. My dad walked to work most days, so the car didn't get used a lot in the heat of the summer. We always had plenty of crawlers around, so I didn't miss them after our Sunday afternoon fishing trip. The following Sunday, when we were heading to church, it was not a church event when the family entered the garage.
Ken