Top 10 Most Beautiful Fish in the World

Mandarin Fish is a saltwater fish belonging to the Dragonet family (Synchiropus), Callionymidae family, Perciformes order. Mandarin Fish is renowned as one of the world's top beautiful fish, often found near coral reefs in the Pacific region. They live near coral reefs, quite secretive, hiding during the day and coming out at night to find mates. Their diet consists of small crustaceans and invertebrates.

Mandarin Fish and its close relative, Synchiropus splendidus, are the only known animals to have blue coloration created by cellular pigments. Males are usually larger and more colorful. Their head and body are a perfect combination of blue, red, and orange. The fish is green, has green and blue colors with orange stripes running along its body. This species is often found in Northern Australia in the Southeastern Pacific. The Mandarin Fish is the most beautiful fish due to its vibrant colors and its tufted dorsal fins.

Clownfish, also known as anemonefish, are marine fish that inhabit coral reefs and rocky outcrops, belonging to the subfamily Amphiprioninae within the family Pomacentridae. There are nearly 28 different species of clownfish. Their bodies are covered in orange color with white stripes. An interesting fact about these fish is that they are all born males but switch to females as they mature. They swim in mesmerizing schools and move very swiftly.

Clownfish are found in warm waters of the Indian and Pacific Oceans, including the Great Barrier Reef and the Red Sea. While some species have limited distributions, others are more widespread. They inhabit shallow marine waters in areas with shelter or shallow tidal pools. No clownfish species live in the Atlantic Ocean.

Clownfish are omnivores and can consume undigested food from their host anemones. Their waste provides nutrients to the anemones. They mainly feed on small planktonic invertebrates from the water column, such as copepods and live tail-end larvae, with some algae consumption as well.

Discus Fish, also known as the 'Five-Colored Fairy' in Chinese culture and revered as the 'Supreme Beauty of Aquarium Fish,' is called the Pompadour Fish, named after the French King Louis XV's Madame Pompadour. The Discus Fish originates from the Amazon Basin. Depending on the different water regions, the fish comes in various colors such as brown, green, red, yellow, and blue.

Wild Discus Fish have four main strains: Heckle, brown Discus, blue Discus, and green Discus. The rest belong to hybrid Discus fish created by hobbyists. Common varieties of hybrid strains are turquoise Discus, and the newest strain is the snow white or albino white Discus. Nowadays, Discus fish come in a wide range of varieties such as turquoise, cobalt, snake skin, pigeon blood, red melon, white butterfly, and albino Discus.

In the ocean, these beautiful small fish are often found in coral reef areas and rocky regions. They are known for their flat, disc-shaped bodies and tend to live in groups, covering themselves among underwater plants where they receive indirect sunlight.

Although listed among the world's most beautiful fish, the Lionfish also possesses venom to fend off its enemies. It's its way of safeguarding its beauty. The fish is adorned with white stripes and red coloration covering its body. It boasts protruding fins that help it swim swiftly in water and capture its prey. The length of the fish ranges from 10 to 15 inches. It can also weigh up to 1.5 kilograms.

Lionfish inhabit tropical waters of the Indian Ocean - Pacific Ocean, but some species can live worldwide. Due to human introduction, Lionfish have recently been seen in warm coral areas of the Eastern Atlantic and Caribbean seas.

Lionfish are known for their venomous fin rays, a rare feature among fish species living in coral reefs along the Eastern Coast of the United States and the Caribbean. The potency of the venom makes them excellent predators and dangerous to fishermen and divers. The venom produces a negative inotropic and chronotropic effect when tested on frog hearts and cockleshells and is effective in reducing blood pressure in rabbits. These results are believed to be due to the release of nitric oxide.

Emperor Angelfish, also known in some places around the world as Imperator or Imperial Angelfish, have a deep blue body, covered with bright yellow horizontal stripes extending up to the top of the head with the tail fin being light yellow to orange. When matured they have a deep blue body with horizontal stripes in bright yellow to orange. The head has a black band running through the eye. When young, they are black with white and blue stripes with circles starting from the tail. In captivity, the coloration of adults may not be as vibrant as in the wild. Angelfish will change their body coloration and patterns throughout their growth.

Emperors thrive in aquariums with a capacity of 220 gallons (880l) or more with plenty of live rocks to provide shelter, hiding spots, and prey capture. They tend to nip at soft coral polyps, other invertebrates. For feeding, it's recommended to supplement with foods containing: seaweed, Spirulina, meaty foods with shrimp content, as well as other meats.

Banggai Cardinalfish or Kaudern's Cardinalfish (Scientific name: Pterapogon kauderni) is a fish species in the Apogonidae family. This fish species is only found in small areas around the Banggai and Sulawesi islands. It is a distinctive marine ornamental fish, with a silver body adorned with black stripes. Its body is covered with small white spots, prominently visible on the dorsal, pelvic, tail, and anal fins.

Feeding them can be somewhat challenging when first introduced into the tank. They can be finicky eaters and may not consume flake or pellet foods initially. Starting with live or frozen fish food and then trying them on vitamin-enriched flake food is recommended. Tank-raised specimens are slightly easier to feed. Multiple individuals can be kept in the same tank if it's large enough. Overcrowding in a small tank can lead to aggression, especially once a pair has formed.

Boomerang Fish, also known as Clown Triggerfish, is a species of fish in the Balistidae family found in the Indian Ocean and the Pacific Ocean, ranging eastward to the Samoan Islands, northward to Central Japan (including the Ogasawara Islands), southward to Australia (including Lord Howe Island) and New Caledonia. In Vietnam, Clown Triggerfish are recorded in Nha Trang Bay and the Spratly Islands.

The Clown Triggerfish has an incredibly striking coloration, making it one of the most popular fish in aquariums. They are typically found along coral reefs in the wild, anywhere where shelled animals and other invertebrates live. They are named Clown Triggerfish due to the markings, as well as the circular spots all over their bodies. The maximum recorded body length of the Clown Triggerfish is 50 cm. They are predominantly black with distinctive white circular spots on the lower half and belly. The back has a prominent lattice-like pattern in yellow. A white or pale yellow stripe lies in front and between the eyes. The area around the mouth is orange with a thin white stripe around it. The tail stem is white, with 3 - 4 rows of small spines; the middle of the tail fin has a light yellow, almost white band. The Clown Triggerfish is of little importance to the fishing industry but is highly prized as an ornamental fish.

Blue-faced Angelfish (Azure Angel Fish) boasts a head color brighter than other parts of the body. Found abundantly in oceanic areas like Australia, Micronesia, and the Indian Ocean. Their lifespan is about 10 years. In this species, color is the measure of development stages. For instance, in the adolescent stage, the fish's body is marked by vertical stripes of black, Sapphire, and white. Upon reaching a developmental threshold of about 12cm, the fish's skin changes to yellow, and at maximum development, it displays light yellow, green scales, and yellow chest fins. The head region features a blue spot with a layer of yellow around the eyes. Particularly, the fish also has a crest on its dorsal fin.

Blue-faced angels are omnivorous and should be fed a variety of foods including both meat and plant-based. They have a particular interest in bloodworms, blackworms, tubifex worms, and similar foods, but will readily consume pellet, flake, and frozen foods. Blue-faced angel fish are considered robust freshwater fish, easy to care for, and adaptable to the environment. This fish has been introduced to Vietnam for a long time and is loved by many, often kept in freshwater tanks.

9. Moorish Idol

Moorish Idol, also known as Moorish fish, is one of the smallest fish species, even in adulthood, the size of this fish remains small. This species inhabits the Indian Ocean and the Pacific Ocean, from the waters of East Africa to the Rapa and Ducie islands, north to southern Japan and the Hawaiian islands, and south to Lord Howe Island. In the Eastern Pacific: from southern California to Peru. Currently, they are one of the tropical fish species migrating to the poles due to climate change, they are capable of moving and invading waters in the South.

This species is characterized by white, yellow, and black striped patterns on the body, making it difficult to distinguish between males and females. They often gather in schools along underwater rock reefs as long as there is a large enough tank. This marine fish is very difficult to adapt and difficult to raise. The long-term existence of this species in home aquariums is rarely seen.

In the ocean, they are herbivorous species feeding on seaweed and sea foam, they are omnivorous animals, including seaweed and sea foam. They are quite picky eaters, and feeding problems can become serious, their protruding mouths can be damaged when picking up and transporting food, when raised, they can eat frozen food or live food for marine fish. They can become sick due to infection with most marine fish diseases especially if they are not eating.

10. Sea Slug

Sea Slug is a common name for marine invertebrates that resemble slugs. Most sea slugs are gastropods, undergoing evolution where their shells are greatly reduced or completely lost. The term 'sea slug' is almost exclusively used to refer to nudibranchs and other shell-less gastropods. They are often found on the seafloor of shallow marine areas.

Sea slugs come in a variety of sizes, colors, and shapes. Many of them are partially transparent. The vibrant colors of those living in coral reefs indicate that they are always threatened by predators, yet it is also a warning to other animals that they are toxic (nematocysts) or have a repulsive taste.

The brightly colored skin is prominently displayed when their shells are lost during adulthood. Nudibranchs, lacking shells, utilize the colorful characteristics of their bodies to blend in with algae, corals, or other marine organisms. This is considered an effective camouflage, potentially confusing predators.