Sea water is pumped continuously throughout the basins to maintain circulation, and the ecology of the water. The glass basins also act as a temperature buffer from the outside conditions, and also represent the role of the ocean as a temperature modulator for the planet. The exterior of the structure also contains rolling curtains to control the UV penetration, while solar cells generate energy to help pump the water and provide lighting.
After the Expo, the pavilion could be reused as a concert hall, theater, museum or even an office building. It’s certainly an extravagant building, but that is the point of World Expos – to design and build feats of wonderment, which is exactly how Paris got the Eiffel Tower.