Thanks partially to the advice of you wonderful folks, and the lifting abilities of my dad, the fish all made it home safe and sound. I was terrified they'd be upset, like Temmers was the first time I moved him--he turned white!--but they seemed largely indifferent. Kefentse mainly occupied himself by posturing at the other two bettas. I had to take them home early because doing so at the end of my exams would've meant lifting it all by myself, which would've been a recipe for trouble. The room feels lonely without them, but they're safe and happy, so it's ok.