Seeing the underwater world in a different light
Apart from tropical rainforests, the coral reef is a rich habitat teeming with the most number of different species. Although they look like flowers, corals are actually well-organised multi-cellular animals. The reef serves as a nursery of many fishes, as well as later pelagics.
During the day, coral reefs present themselves in a variety of colours, thanks to the corals and the animals that live there. A night dive at a reef immerses the diver in a magical world filled with many different colours and hues – it is an enchanting experience.
What this means is that it is the ideal site for fluorescence, or fluo dives, at night.
It is in such a situation that the corals and other animals (like crabs, tubeworms, fishes, etc) glow in an array of rainbow colours, It is an experience that makes you feel like you are an alien world, or at least a parallel universe with an altered colour spectrum. Think Avatar – underwater.
What are fluo dives?
In fluo diving, short-wave, high-energy light (ideally blue light with a wavelength of 450 to 465 nm) from special ultraviolet flashlights is shone at the animal or coral. The organism absorbs the light. If it has any fluorescent dyes, the light is reflected back as long-wave, low-energy light. Viewing the scene through special lens filters in your mask causes the burst of stunning colours embodied by the organisms to be bathed in a mystifying glow of stunning colours.
What equipment do you need?
For an introductory fluo dive, all you need is blue fluorescent lighting and a yellow mask filter, and some experience in night diving. On subsequent dives, you may want a camera with underwater housing and yellow filters. Presently, there are already some cameras that are waterproof up to 15 metres, so you may not need the additional underwater housing. In the professional range, the prices for the entire set (which includes fluorescent light, barrier filters for the masks and a good camera) start at about 250-300 Euros and for professional equipment can be well over 1,000 Euros.