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49. A safe haven for a shoal of Glassfish


A Black Coral bush provides a safe haven for a shoal of Glassfish.

These small fish are extremely vulnerable to predation and will always be found close to an area where shelter is provided by nature. Swimming around the bush-like coral colony, they will retreat to the safety of the cnidarian at the slightest sign of insecurity.

These lush bushes belong to the family of black corals (Antipatharia) and are a coral species found in the deeper parts of our oceans around the world. They get their name from their black skeleton that remains after the animal has died and has lost all of its colourful polyps. Almost all shallow water corals turn white, the colour of their limestone skeleton, when deceased.

Black Coral is not a single species but an order with 7 families and more than 280 species distributed over 44 genera.

Unlike most corals that rely on sunlight to produce energy, black corals are carnivorous, feeding on a variety of drifting tiny organisms such as zooplankton. Predation happens through the use of their mucus and their nematocysts (stinging tentacles). They prefer darker and current-swept habitats and inhabit the deeper parts of coral reefs, often found at depths of 30m/100ft to at least 1000m/3000ft. Sometimes they can form dense aggregations on hard and rocky surfaces or on wrecks and walls of underwater canyons.

The name glassfish is a collective noun, referring to the family of Ambassidae (Asian Glassfish), transparent and semi-transparent small fish from the Indian and Pacific Ocean. There are about 51 different species in this family, with the largest one reaching a total length of about 26cm/10 inches. Identification of these dense shoals of little translucent fish is extremely difficult. Some of these fish aggregations might not even belong to the Glassfish family but could just be a school of juveniles of another known species taking shelter amongst the branches of a Black Coral bush.


In my opinion, a wide-angle scene is best filmed with a steady shot. Moving around with your camera on a wide-angle scene will produce distortion on both sides of your frame, often seen in GoPro shots. This distortion is more likely to occur when the camera is moved while filming or when the angle is set too wide in comparison with the size of the subject.

The purpose of a wide-angle setting (or through the use of a certain lens or dome, or digitally in your camera’s menu) is to film a really wide scene, such as an entire section of a coral reef, a big wreck, or big animals like whales or schools of sharks. If you use a wide-angle setup to film a small subject, you will probably end up with some form of distortion in your footage. Luckily, there are easy techniques to avoid these distortions and ways to correct them in post-production.

I added the sound of wind chimes in the final product to accentuate the sudden movement of these little fish. For swarming fish, you can also use whoosh sounds.

Filming location:

This short underwater videoclip has been filmed in the Maldives 🇲🇻

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