Yeah, same here.

To elaborate on Aristos explanation: For the ball to enter from below you have to push water aside/upwards. The water, being heavier than the ball, wants to take back its original "deep position" (least potential energy) so it pushes the ball upwards in the process.
Each ball that pulls the chain up has to pull in another ball and friction aside these energies equal each other. Law of conservation of energy is safe once again.