I have all of my snakes in 32 qt tubs including my big girls. I have been pairing and getting locks without any issues. I don't see an issue with pairing in a 32 qt tub or a 41 qt. Your boy\girl or both may just not have been mature enough last year is all. I would just keep pairing on a 3 day on 3 day off schedule and offer food once per week. I just wait a day or so after feeding if they are due to be paired. I don't wait for defication. Hope that helps. Good Luck!![]()