The occurrence of fluorescence in some coral species was discovered by Dr Catala and his wife, founders of the Aquarium, in 1958.
The corals you see here were collected between the surface and depths of 35m, both inside and outside the lagoon. In the display, they are subjected to black-light to bring out the fluorescence, caused by certain pigments present within the tissues of the living coral, which react with ultraviolet light.

The blue-green lights you will observe in the far tank are produced by "flashlight-fish". These fish have developed, under each eye, a specialised organ capable of emitting this faint light, actually produced by symbiotic bacteria through a light-generating chemical reaction. This ability to shine is primarily used by the fish to attract prey, but also to fool pursuing predators by 'turning the light off' and then making a quick turn.