Get your Wednesday started off on the right foot: load this video up in HD, full-screen, let it buffer, and then just watch for awhile. You'll feel right as the mail.
The main tank [at the Okinawa Churaumi Aquarium in Japan] called the "Kuroshio Sea" holds 7,500-cubic meters (1,981,290 gallons) of water and features the world's second largest acrylic glass panel, measuring 8.2 meters by 22.5 meters with a thickness of 60 centimeters. Whale sharks and manta rays are kept amongst many other fish species in the main tank.
This tank is the second largest aquarium tank in the world.
Update: From the same aquarium: Jellyfish.