Rainbow Shark Size: Deep Diving Into Shocking Shark Sizes!

Abhijeet Modi
Oct 27, 2023 By Abhijeet Modi
Originally Published on Nov 25, 2021
Rainbow shark in a tropical aquarium.

Watching a rainbow shark glide smoothly in your aquarium is a peaceful sight, but have you ever wondered what the different sizes that these fish come in?

Rainbow sharks are also known as ruby sharks, red-fin sharks, red-finned sharks, green fringe-lip labeos, whitefin sharks, whitetail shark minnows, and rainbow shark minnows. They are a species of semi-aggressive aquarium fish with sleek black, dark blue, or brilliant blue bodies, pointed snouts, and flat abdomen areas.

Rainbow sharks are found in the Indochina River basins where they reside in water with sandy substrates close to the river bottom and feast on algae as well as plankton. They travel into flooded regions seasonally and then return to the rivers when the floods subside.

Fish have lived on the planet for almost 450 million years, while mammals have only been around for about 200 million. On the planet, there are about 27,000 known fish species, 1,000 shark species, and an estimated 15,000 fish species that have yet to be documented.

Collectively, fish species outnumber amphibians, reptiles, birds, as well as mammals collectively. The rainbow shark (Epalzeorhynchos frenatum) is a freshwater fish from Southeast Asia that belongs to the Cyprinidae family.

The rainbow shark is an actinopterygiian, which means 'ray-finned fish', as opposed to actual sharks, which are Chondrichthyes, which belong to the cartilaginous fishes' lineage. The fins have a bright crimson to orange-red hue.

A distinctive short stripe runs from the cover to the eye and from the eye to the mouth. Male rainbow sharks have slimmer bodies and black stripes running along with their tail fins as compared to females.

Males have a stronger color as well. They can reach a length of around 6 in (15.2 cm).

The rainbow shark is one of the most misunderstood aquarium fish, particularly among aquarium novices. As a result, it's critical to clear the air and discover the right facts.

Afterward, also check out do sharks have tongues, and do sharks have bones?

Rainbow Sharks Biology And Breeding

Fish are popular pets, and certain varieties are quite easy to care for. Aquariums are glass tanks where pet fish are kept. Because certain fish prefer warm water, the aquarium will require an underwater heater that will turn on and off automatically to maintain the proper water temperature.

The water is kept flowing by an air pump, and the water is kept clean by a specific filter. To keep fish healthy, tiny amounts of food must be given to them on a daily basis.

Try cleaning the aquarium on a regular basis, and replacing part of the old water with fresh water. Rainbow sharks are known for their distinctive appearance and striking similarity to enormous ocean sharks. Despite their popularity, these colorful fish can be challenging to maintain.

Rainbow sharks belong to the class Actinopterygii, order Cypriniformes, family Cyprinidae, and genus Epalzeorhynchos. The rainbow shark, also known as the red-finned or ruby shark, is a Southeast Asian species.

They are not sea fish, but rather freshwater fish. They are found mostly in the rivers of Myanmar, Thailand, Laos, and Malaysia. Rivers with sandy bottoms and abundant plankton are their favorites.

During seasons of heavy rain or floods, they have been known to move towards floodplains. True sharks are not rainbow sharks.

Instead, they were given their name because of their dorsal fin on top, which gives them a shark-like look. Epalzeorhynchos frenatum is a Cypriniformes species that belongs to the Cypriniformes order. As a result, this species is commonly classified as a freshwater shark that may be kept in a range of fish tanks.

This species was historically common in the Southeast Asian seas, but populations have declined in recent years. Scientists think that damming particular rivers, such as the lower Xe Bangfai, has resulted in a decrease in rainbow shark populations in recent years.

Rainbow sharks are known to deposit eggs. However, in an aquarium setting, reproduction is challenging.

Commercial farms in Southeast Asia are engaged in breeding rainbow sharks in large numbers. River dams may reduce floodplains, interfering with the mating cycles of the ruby shark. Because almost all commercially available rainbow sharks come from farms in Thailand, aquaculture has little impact on their populations in the wild.

Are there different types of rainbow shark?

Rainbow sharks are recognized for their bright red fins, which are the origin of their name. Their fins, in addition to being red, can sometimes take on an orange color. Their brightly colored fins, like that of a red-tailed shark, pop against their gray or black bodies, which are typically long and thin.

A dark blue body is also seen in certain rainbow sharks, though it is less frequent. The dorsal fins of this fish can have up to 11 branching rays, while the tail fin is forked.

The face of the rainbow shark is very flat, with a rounded nose in front. Two eyes, one on each side of the head, seem to be sunken rather frequently.

The rainbow shark's body is rounded towards the head and rear, then tapers off as it approaches the tail. Males and females have distinct color differences.

Males, for instance, exhibit brighter red or orange fins than females. Males' tail fins will also have tiny gray lines, whilst females' fins will be free of lines.

Rainbow sharks' bellies are likewise thicker and much more rounded in females. Because there is little difference between young male and female rainbow sharks, these differences become obvious as the fish age.

Because reproducing rainbow sharks is difficult, there aren't many distinct types. Albino versions are the only other varieties known.

Albinos are a very rare breed. As long as they are the only sharks in the tank and the remaining tank mates are of comparable size, the Albino Rainbow Shark, often known as the Albino Ruby Shark or Albino Red-Finned Shark, is ideal for the semi-aggressive community tank.

The Rainbow Shark is a pink shark with brilliant red fins and crimson eyes.

The rainbow shark features red fins. However, this fish has a white body instead of blue or black patterns. The body of an albino rainbow shark can sometimes turn a bright pink or yellow color.

The albino rainbow shark's light-colored body contrasts with its brilliant fins to create a unique, but nevertheless highly sought-after appearance. A huge aquarium containing driftwood, rocks, and lush vegetation is required.

This shark has the potential to establish territories throughout the aquarium. When grown, the rainbow shark becomes extremely violent toward its own kind.

The Albino Rainbow Shark's mating patterns have not been reported. The Albino Rainbow Shark is an omnivorous fish that doesn't mind eating a wide variety of foods. You can feed them flake food, freeze-dried bloodworms, tubifex, and vegetable-based products.

Rainbow Shark Size Vs Other Sharks

When it concerns shape and size, the fundamental difference between males and females would be that males are somewhat slenderer. Rainbow sharks are tiny specks as they hatch from their eggs.

From there, they expand at a quick pace, reaching a large size. There’s no doubt that certain sharks are truly marine behemoths, from great whites to whale sharks. But, in comparison to humans, how do sharks fare?

Upon reaching adulthood, a rainbow shark is normally 6 in (15.2 cm) long. Several have expanded to be as long as 8 in (20.3 cm) in length, but they are the exceptions. This size applies to both regular rainbow sharks and albino rainbow sharks. Males and females are around the same size in terms of length.

Sharks come in a variety of sizes, from the size of a human hand to the size of a car. The whale shark is the largest shark, with a length of up to 46 ft (13.9 m).

The spined pygmy shark is the tiniest shark, measuring about 8 in (20 cm) long when fully grown. Most sharks are of average size, measuring 5-7 ft (1.5-2.1 m) long and roughly the same size as humans.

Half of the 350 shark species have a length of less than 39 in (99 cm).

The majestic whale shark, which measures 56 ft (17 m) and is 10 times the length of humans, redefines the term 'gentle giant' in our seas. Despite this, these massive filter feeders are quite safe to dive with, and their kind attitude makes them one of the most popular sharks to dive with.

Some of the largest whale sharks may weigh up to 30 met ton (66,138 lb), which is four times the weight of an African bull elephant.

Basking sharks with jaws that can expand over 3.2 ft (1 m) wide have one of the most amazing mouths, with jaws that can open up to 50 ft (15 m) wide.

The megamouth shark, at 24.7 ft (7.5 m) long, is notable for its huge mouth, which it utilizes to ingest tonnes of plankton in one massive gulp, similar to basking and whale sharks.

The largest Greenland shark ever documented was 24.1 ft (7.3 m), but because so little is known about the Greenland shark, experts believe there might be even larger specimens in the deep.

Great white sharks are incredibly powerful predators due to their size, strength, and more than 300 razor-sharp teeth. Mature great white sharks are around 14.8 ft (4.5 m) long on average, although they can grow to be up to 19.8 ft (6 m) long.

While great white sharks are among the ocean's top predators, they are not naturally violent toward humans and strike out of sheer curiosity rather than a desire for a meal.

For understandable reasons, the otherworldly great hammerhead shark, measuring 19.8 ft (6 m), is one of the most distinctive shark species.

These strange organisms, which are native to tropical waters, feed on the bottom, utilizing their keen vision and electrical impulses to chase their preferred prey, stingrays. The 19.8 ft (6 m) long bluntnose sixgill shark is the biggest species of fossil shark, a group of prehistoric marine organisms that have existed since the Jurassic period.

Another shark commonly seen in UK waters is the common thresher shark, which measures 18.1 ft (5.5 m) and belongs to the thresher family, which is known for its large tail fins.

The common thresher is the biggest of the thresher species, with a tail that is longer than the typical person. It is found across the world's seas, save in the polar areas.

The 10.5-foot (3.2 m) long sand tiger shark is a calm, slow-swimming shark native to the continental shelf's subtropical and temperate seas. It is commonly observed in the oceans of Japan, South Africa, and sections of the Mediterranean.

Lastly, the dwarf lanternfish, the world's smallest shark species, demonstrate shark biodiversity. This little-known species is a sort of dogfish shark that grows up to 8 in (20 cm) long and is only found on the continental slopes of Colombia and Venezuela.

Average Rainbow Shark Size

A rainbow shark's usual lifetime is between four and six years, while some have been known to survive up to eight years. That's a lot longer than other aquarium fish, such as bettas, which can only survive for two years.

It is, however, a fraction of the lifespan of goldfish, which may live up to 20 years. The quality of your tank's water will determine how long your rainbow shark lives.

At full adulthood, a rainbow shark is normally no more than 6 in (15 cm) long. Some have grown to be as long as 8 in (20.3 cm) in length, but they are the exceptions. This size applies to both regular rainbow sharks and albino rainbow sharks.

They're territorial fish with a proclivity for aggressive behavior toward smaller fish. Males and females have similar lengths.

Males are somewhat slimmer than females in terms of form and size. Rainbow sharks are only tiny specks as they hatch from their eggs. They quickly grow from there.

Dietary Requirements And Feeding Your Rainbow Sharks According To Their Size

Rainbow sharks are omnivores who eat a lot of algae, larvae, and scraps of flesh in their native habitat. They'll devour any algae that accumulate naturally at the base of your rainbow shark aquarium. If there aren’t adequate algae within your tank for them to eat, you may offer them algae in tablet, flake, or wafer form.

Despite the fact that algae are a regular element of the rainbow shark's diet, they need a well-balanced diet.

Frozen solid bloodworms, fish pellets, brine fish, bug larvae, tubifex worms, crustaceans, as well as aquatic insects are some wonderful feeding choices that they'll appreciate and that will encourage them to stay healthy. You may also throw in some diced cucumber, raw peas, or spinach pieces for some more flavor.

In an ideal situation, you may feed your fish a range of plant and animal matter. Feedings should be done at regular intervals, perhaps two or three times each day. Make sure your rainbow shark doesn't get too fat.

Offer your fish only as much as they can eat in a single meal, and don't try to make up for missed meals by giving more. When the ruby shark is still a juvenile, it's very vital to pay attention to its food.

To guarantee optimum development and color, feed juvenile sharks a variety of plants. If your rainbow shark doesn't get enough vegetation when it's young, its growth will be hindered, and its fins won't be as vividly colored as they should be, so ensure that doesn't occur.

The Best Aquarium Size For Rainbow Sharks

When it comes to rainbow shark care, there are a few things you should keep in mind. Overall, they're hardy little fellas that don't require a lot of attention, but they do need their basic needs met.

A tank of size 50 gal (190 l) is perfect for a rainbow shark. This will definitely rise when the population of other fish in your tank grows, but we don't think you should go smaller than this.

If you went smaller, it would be unfair to them and any other fish you wanted to keep in the same tank. Rainbow sharks require room in order to grow and feel in command of their domain or tank area.

If you're only maintaining one fish, the rainbow shark tank should be at least 4 ft (1.2 m) long and 18 in (45.7 cm) broad. This will provide plenty of space for your rainbow shark to swim in.

They're more prone to growing angry and feeling constrained if they don't have adequate horizontal space. This tank size will also allow you to add caves, rocks, and other items for it to explore and hide in.

Naturally, you should leave at least a few inches of room at the top to permit the tank's oxygen supply.

When estimating how many gallons of water your tank can contain, keep the criteria in mind that you should always go with a larger tank size if you're unsure. A 50 gal (190 l) tank is suggested, but a 55 gal (208.3 l) or bigger tank will give you the best results.

How to provide the optimal environment?

Rainbow sharks are known to be violent toward other fish that resemble them. This is one of the reasons why red-tailed sharks and other sharks should never be kept together in the same aquarium, as a red-tailed shark looks very similar to it.

Rainbow sharks can be hostile towards one another at times. It's possible that one of the fish is attempting to exert control over the others.

As a result, if you want to possess multiple rainbow sharks, you may wish to include at least five of these beautiful fish. That number gives the dominant rainbow shark more fish to pick on, ensuring that no one species gets more attention than it deserves.

Rainbow sharks live towards the bottom of rivers in their natural environment. This implies they prefer to live towards the bottom of their tanks, where they may claim caves, tunnels, or any other hiding spaces.

Rainbow sharks should not be kept with tank mates that like to hang out on the bottom, such as Bala sharks, Red-tail sharks, Cichlids, and catfish. Instead, consider species like Rasboras, Danios, Gouramis, rainbow fish, and loaches that live at the center or top of the tank and can defend themselves if necessary.

Because of their semi-aggressive character, putting other fish in a tank with rainbow sharks is always a danger. To avoid this, start with the other fish in your tank and then add your rainbow shark last.

As a result, your shark is less likely to regard the aquarium as his territory. When the other fish are the same size or larger than your rainbow shark, you're less likely to see hostility.

Rainbow sharks are known to be violent toward other fish that resemble them. This is one of the reasons why red-tailed sharks and other sharks should never be kept together in the same aquarium.

Here at Kidadl, we have carefully created lots of interesting family-friendly facts for everyone to enjoy! If you liked our suggestions for rainbow shark size then why not take a look at do sharks make noise, or rainbow shark facts.

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Written by Abhijeet Modi

Master of Computer Science

Abhijeet Modi picture

Abhijeet ModiMaster of Computer Science

An experienced and innovative entrepreneur and creative writer, Abhijeet holds a Bachelor's and Master's degree in Computer Application from Birla Institute of Technology, Jaipur. He co-founded an e-commerce website while developing his skills in content writing, making him an expert in creating blog posts, website content, product descriptions, landing pages, and editing articles. Passionate about pushing his limits, Abhijeet brings both technical expertise and creative flair to his work.

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