[2] The game was later ported to Microsoft Windows under the name Aquarium and was released in Europe on 25 December 2000.

In Theme Aquarium, the player begins with an expanse of empty floor space and the task is to construct a maritime attraction for visitors which must be filled with interesting and appropriate creatures at the same time as dealing with all the attendant challenges of running a profitable business.

Staff must be hired to maintain the aquarium and also to take proper care and attention to the animals.

In a 1999 interview, Bullfrog Productions co-founder Les Edgar stated that Theme Aquarium was produced and tested in the United Kingdom, but implemented in Japan.

[4] In 2012, Bullfrog programmer Jonty Barnes asked fourteen ex-colleagues about the game, none of whom were familiar with it, with one describing it as "one of those obscure titles", although he also stated that it was known that it was intended for a Japan-only release on the PlayStation.