In the 1920's a large ballroom was build in the back of the aquarium for dacing was very fashionable back then. After the war (military used the aquarium) the whole thing was a bit neglected and in a bad state.
In 1967 the first dolphins arrived. They used to be in a small pool near the entrance (today the giftshop). But because they were so popular, they build a bigger show-tank, at the location of the ballroom.
The last couple of dolphins left for the Turks and Caicos islands when sea life to over the aquarium (somewhere in the 1990's i guess?). After that the show-tank was turned into a coralreef with sharks, green turtles etc. Very well done! You can see them from above but also under water (including through a standard sea life glass tunnel)
