The adoption of an appropriate theme which weaves an identifiable thread through the exhibits is considered essential to a successful display. This is the framework upon which most aspects of the aquarium are draped. This may include architecture character, interior decoration, exhibitory, relationship to the environment, conservation or marketing and merchandising.

The theme is usually developed with particular reference to specific regional character or iconic displays but can be much wider. It reinforces the diversity and abundance of marine and freshwater species, habitats, flora and fauna exhibited and their inter relationship with the environment.

The following are some examples of aquarium themes:

Underwater World Mooloolaba Australia – Adaptations

Cairns Undersea World Australia – Coral Reefs

Manly Ocean World Australia – Ocean Predators

Hualien Ocean Park Aquarium Taiwan – Discovering Ocean Predators

Osaka Aquarium Japan – Ring of Fire