Magical Fluorescing Corals

Published May 23, 2013 in DIVING & SNORKELING, Fluo-diving, MARINE LIFE, Underwater Photography

Wakatobi has some of the most pristine coral reefs on the planet, and some of the only reefs that are actually thriving, getting healthier, richer and more diverse each year. Divers come from around the world to immerse themselves in Wakatobi’s coral gardens, and to take in the visual feast these reefs provide.

Recently, science has provided divers with a whole new way to see coral reefs like never before. It turns out that many corals have a hidden ability to reflect light in spectrums that are not visible to the human eye, but can be revealed through the use of special blue UV light lighting. After dark, when sunlight no longer competes, this special lighting brings corals to light in glowing, otherworldly colors. We call it Fluo-Diving.

Fluo-Diving reveals the hidden florescent abilities of certain marine life. Not to be confused with phosphorescence or bio-luminescence, fluorescence is the ability to absorption of one wavelength of light and the re-emission of a totally different wavelength of light. When a fluorescent object is seen under sunlight, it appears normal. But when struck by a near-UV light source, it absorbs the blue light spectrum and re-emits a fluorescence that transforming the blue into a brightly-glowing, totally different color.

soft coral polyps_liquid motion film

Soft corals take on a whole new light under the cover of darkness and UV-light source. Photo by LIquid Motion Film

Anyone who has ever seen hidden colors appear under a ultra-violet lamp, aka a “black light,” will understand the principles of marine florescence. And just like those black light posters on college dorm walls, some types of coral, fish and marine life will be revealed in glowing, otherworldly hues when seen under a special type of blue lighting.

The following video – Fluorescent Corals, produced at Wakatobi, illustrates how two identical corals, side by side, behave in completely different ways. Using our special fluo-lights, one fluoresces back a bright green color, the other fluoresces bright pink or yellow, or doesn’t fluoresce at all!

Corals on Fluo

Though they don’t reveal their secret abilities during daylight hours, corals can take on an other-worldly glow in low light or darkness, when illuminated by a deep blue light source. This phenomenon is thought to be a type of communication, but scientists are still researching the whys of marine fluorescence, and there are many questions to be answered.

“Fluo-diving was incredibly interesting. Diving with a black light and filters on our masks was exhilarating, but the fluorescence of marine life was beyond our wildest dreams. Seeing the fluorescence of corals and other marine life at night leads us to wonder why?”  Eva and John Centanni

One of the most interesting recent discoveries is that coral fluorescence can serve as an indicator of the overall health of a coral reef. A study conducted by the Scripps Institution of Oceanography showed that numerous Indo-Pacific reef building corals showed a marked decline in florescent ability when subjected to stresses such as elevated temperatures that could cause coral bleaching.  As numerous guests can attest, the reefs of Wakatobi display their good health through vigorous fluorescent activity.

While still not fully understood, fluorescence has already become an important tool for biomedical research, as it can be used to study changes within living organisms. One of the most important such discoveries came from a type of tube anemone that fluoresces only under a very specific wavelength of light. By isolating the protein that makes this anemone glow, researchers now hope to use this ability to switch florescence on and off to delve deeper into the inner workings of cellular biology.

Read more about the phenomenon of Fluo-diving and Fluo-snorkeling on Wakatobi’s reefs here.

Fluo-diving and snorkeling is conducted with a private guide as a one-on-one or buddy-diving experience. Guests of Wakatobi Dive Resort can make arrangements with the resort staff or the concierge.

For more information on a Wakatobi trip with Fluo-diving / snorkeling, complete our trip inquiry at Or email