[Kenichi looks at the gems and the tanks. At both Regis and Finn's answers, he nods.]

Hmmm, water and promise are probably the answers like you guys said.

Still, I wonder if there's a connection to the fish in the tanks, the answers to the riddles and those gems. I'll keep track for us just to be safe. This really has to be the most convoluted security measure, I've ever seen though.