1. Mandarinfish
Not to be confused with Mandarin Fish (Chinese Perch). The mandarinfish or mandarin dragonet (Synchiropus splendidus), is a small, brightly-colored member of the dragonet family, which is popular in the saltwater aquarium trade. A lesser-known species, these are probably the single most colorful and vibrant fish I’ve ever seen. The mandarinfish is native to the Pacific, ranging approximately from the Ryukyu Islands south to Australia. Yes! They are definitely the most colourful fish in the world.
2. Juvenile Emporer Angel Fish
This a very famous fish known to non-divers more than the divers. However most of them don’t know the different between the youngs and the adults of these kinds. Juveniles are most fascinating fish in the waters. They are dark blue with electric blue and white rings; adults have yellow and blue stripes, with black around the eyes. It takes about four years for an emperor angelfish to acquire its adult colouring. They grow to 40 cm (15.75 in) in length.
3.Lion Fish
The lionfish is one of the most venomous fish on the ocean floor. Lionfish have venomous dorsal spines that are used purely for defense. When threatened, the fish often faces its attacker in an upside down posture which brings its spines to bear. However, a lionfish’s sting is usually not fatal to humans. If a human is envenomed, that person will experience extreme pain, and possibly headaches, vomiting, and breathing difficulties. However they are one of the most beautiful and colorful fish.
4. Clown Trigger Fish
Triggerfishes are about 40 species of often brightly colored fishes of the family Balistidae. Often marked by lines and spots, they inhabit tropical and subtropical oceans throughout the world, with the greatest species richness in the Indo-Pacific. Most are found in relatively shallow, coastal habitats, especially at coral reefs, but a few, such as the aptly named oceanic triggerfish. One of the most beautiful of their species is the clown trigger fish, it’s designs and colours are literally breathtaking!
5. Nudibranch
A nudibranch is a member of what is now a taxonomic clade now, rather than a fish. Nudibranchs are often casually called “sea slugs“, a non-scientific term. This has led some people to assume that every sea slug must be a nudibranch. Nudibranchs are very numerous in terms of species, and are often very attractive and noticeable. Among this group can be found the most colorful creatures on earth.
6. Symphysodon
All Symphysodon species have a laterally compressed body shape. , however, extended finnage is absent giving Symphysodon a more rounded shape. It is this body shape from which their common name, “discus”, is derived. The sides of the fish are frequently patterned in shades of green, red, brown, and blue. The height and length of the grown fish are both about 20–25 cm (8–10 in).
7. Mantis Shrimp
Mantis shrimp appear in a variety of colours, from shades of browns to bright neon colours. Although they are common animals and among the most important predators in many shallow, tropical and sub-tropical marine habitats they are poorly understood as many species spend most of their life tucked away in burrows and holes. Although it happens rarely, some larger species of mantis shrimp are capable of breaking through aquarium glass with a single strike from this weapon.
8. Moorish Idol
One of the most difficult fish to keep in a home aquarium (and very expensive as well), to most aquarists Moorish idol are the pinnacle of the hobby. You may think you’ve seen them before, but you’re probably getting them confused with another species, the Bannerfish (also known as the False Idol). With distinctively compressed and disk-like bodies, moorish idols stand out in contrasting bands of black, white and yellow which make them look very attractive to aquarium keepers.
9. Clownfish
Also known as Anemonefish, Clownfish are some beautiful fish which generally consist of a yellow/orange body with white stripes along with black lining along it’s fins or black body with yellow/orange areas along it’s lower body and fins , though this depends upon the species of Clownfish and they come in various displays. Many show white bars or patches. The largest reach a length of 18 centimetres (7.1 in), while the smallest barely reach 10 centimetres (3.9 in).
10. Rainbow Parrot Fish
Named Parrot fish because of their calcareous bird-like beaks. Parrot fish use these beaks to crush and eat the small invertebrates that live in coral. Much of the sand and sea floor of coral reefs are actually remains of meals from the parrot fish, they chew the coral, eat the invertebrates and spit out the leftover calcium. In most species, the initial phase is dull red, brown or grey, while the terminal phase is vividly green or blue with bright pink or yellow patches. The remarkably different terminal and initial phases were first described as separate species in several cases, but there are also some species where the phases are similar.
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