Made curious by the way the symbolist painter Odilon Redon referred to his images of the underwater world as "aquariums", Ursula Harter set off in search of answers to the questions: When were the first "aquarium buildings" constructed, what did they look like, and how were they received? Aquariums are popular eye-catching props in window displays as well as onstage in the theater. As an interactive feature they add interest to art exhibitions, beautify washrooms, and temper the dreariness of subterranean pedestrian passageways. Anyone who is averse to the level of dedication needed for their maintenance can instead opt for the on-screen version, which has been added as optical background music to the decoration scheme of many banks, luxury boutiques and hotels, shopping malls, cafés, restaurants, and night clubs. Aquariums tend to serve nowadays solely to set esthetic accents, their presentation often attesting to contempt for the living creatures within them and the commercial exploitation of nature as a "product". This publication is supported by Ernst von Siemens Kunststiftung.