Iridescent Shark: Care, Growth Rate, Size, & More

Hello, fellow aquarium enthusiasts! I am thrilled to share my knowledge on caring for these beautiful creatures, including tank maintenance, feeding habits, and behavior analysis.

With their shimmering scales and potential growth rate of up to 3-4 feet in length, they are sure to catch the eye of anyone who walks by.

However, it is important to understand their basic care guidelines before diving into the world of iridescent shark ownership.

This article will explore tank requirements, diet and feeding habits, and tips on breeding these fascinating creatures.

Natural Habitat & Basic Characteristics


The iridescent shark catfish (Pangasianodon hypophthalmus) is a captivating creature native to Southeast Asia’s rivers.

Not a shark, this family member of the Pangasiidae is heavily cultivated for food in the Mekong and Chao Phraya basins and is known as swai or sutchi catfish.

Its diet of crustaceans, fish, and plant matter has made it popular among fish keepers.

This species has a unique appearance, with juveniles having a black stripe on the lateral line and a second one below it.

The most striking feature, however, is the iridescent hue that gives the fish its name.

The swai’s popularity is due to its remarkable coloration, making it beloved among hobby aquarists.

Its omnivorous diet and introduction to other river basins for food make it a valuable source of sustenance.

The iridescent shark catfish is an awe-inspiring creature that will make a splash in any aquarium.

I’ve always been fascinated by iridescent sharks. They have a unique appearance with their dark, shiny skin and sail-like dorsal fin.

Their skin transitions to a solid grey as they age, but albino varieties with white bodies and red eyes are highly sought after.


They’re known for their distinctive “catfish” look, thanks to their long barbels that help them find their way in murky waters.

If you look closely, you’ll notice they have quite large eyes – especially when they are younger.

As they age, the eyes seem to grow into their head.

The tail fin of an iridescent shark is quite remarkable, as it has a sail-like texture similar to the dorsal fin.

Meanwhile, their anal fins extend from the flat belly to the bottom of their caudal peduncle.

To tell if an iridescent shark is male or female, the best indicator is size, and females tend to be wider and less streamlined than males.

Albino Iridescent Shark


Albino iridescent sharks are a fascinating subtopic in the discussion of their appearance.

These fish have a unique white body with striking red eyes, making them highly sought after by collectors.

Compared to their darker counterparts, albino iridescent sharks stand out and contrast to any aquarium setting.

Finding an albino version of this sought-after freshwater fish can be challenging due to their popularity, but they’re stunning.

The only difference between the albino iridescent shark and the regular one is that it’s white with red eyes.

It’s important to note that the genetics of albinism in sharks can make them more prone to illness and disease, so it’s crucial to care for these unique creatures properly.

Breeding feasibility for these fish is low, so most will only be available through selective breeding or natural mutations occurring in the wild.

Availability in pet stores will depend on your location and local demand, but they tend to come with a higher price range due to their rarity and beauty.


To ensure your iridescent shark thrives in its home aquarium, it’s important to give them plenty of space as they can grow up to 3-4 feet in length.

It’s crucial to remember that their growth rate can be quite fast, so make sure you have a tank that can accommodate their size as they mature.

Compared to other freshwater fish, the iridescent shark is a large fish that requires ample room for swimming and exploring.

The key takeaway is giving your iridescent shark enough room to grow comfortably throughout its lifespan.


If taken care of properly, the iridescent shark can live up to 20 years in captivity.

Factors affecting their lifespan include diet, water quality, tank size, and overall environmental impacts.

Monitoring their behavior closely for any changes or signs of illness is important.

Providing a well-balanced diet with micronutrients is crucial for maintaining their health as they age.

Regular water changes and keeping the tank environment clean also play a role in prolonging their lifespan.

Your iridescent shark could be your loyal companion for many years with proper care and attention.

Basic Care Guidelines

Caring for iridescent sharks is relatively straightforward. The tank parameters, food, and tank mates are easy to manage.

The biggest challenge to deal with is their size. These fish can get huge and require a large enough tank to stay healthy and comfortable.

When people purchase these fish, they often need to pay more attention to their size and think a 40-gallon tank is enough.

When the fish begin to grow, it throws off their entire care plan.

Before investing in an iridescent shark, it’s important to read up on their care essentials. Then honestly assess if you’re ready to provide for them as they grow.

Tank Size Requirements

For a healthy and happy schooling environment, iridescent sharks require ample space in their tank.

A 300-gallon tank is the minimum size required for these fish to thrive.

It’s important to keep the tank in a quiet house area and maintain proper water parameters such as pH levels, water hardness, and temperature.

Additionally, filtration systems are crucial for maintaining good water quality.

The filter requirements will depend on the size of the aquarium and the number of fish but should provide enough water circulation and oxygenation.

To mimic their natural habitat, driftwood, and rocks should be added to the base of their tank. Plants are not necessary but can also be added as decoration if desired.

Proper tank decor helps create hiding places for iridescent sharks, reducing stress levels while allowing them to explore their surroundings.

Keeping at least four iridescent sharks together is recommended since they are schooling fish that prefer companionship.

Tank Setup Recommendations

Creating the perfect environment for your iridescent shark is crucial to its happiness and longevity.

Here are three tips to help you create an ideal environment for your iridescent shark:

  1. Decor options: To mimic their natural habitat, driftwood, and rocks should be added to the base of their tank. These decorations provide hiding places and serve as a source of nutrients for beneficial bacteria that support the nitrogen cycle in the aquarium.
  2. Filtration systems: A high-quality filtration system is essential to maintain clean water and remove waste from the tank. Canister or power filters with biological, mechanical, and chemical filtration capabilities are recommended.
  3. Lighting choices and substrate selection: Iridescent sharks prefer dimly lit environments, so they avoid exposure to bright lighting or direct sunlight in their tank. As for substrate selection, sand or gravel should be used instead of bare-bottom tanks as they provide a more natural environment and encourage beneficial bacteria growth.

Following these tips, you can create a comfortable home for your iridescent shark that mimics its natural habitat while providing all the necessary elements for its survival.

Remember that happy fish lead to healthy fish!

Water Parameters

Maintaining proper water parameters is essential for the well-being of your iridescent shark and can impact its overall health and lifespan.

Water filtration is essential in keeping the tank clean and free from harmful toxins.

A good quality filter that can handle a large volume of water should be used, along with regular cleaning, to prevent clogging.

The filter should also be appropriate for the size of the tank.

Water changes are also necessary to maintain healthy water parameters.

Unregular water changes can lead to an accumulation of waste, which can harm your fish’s health.

A 25% water change once every two weeks is recommended, but this may vary depending on your tank size and number of fish.

Regular pH testing should also be done using test strips or a digital meter to ensure it stays within the range suitable for iridescent sharks (6.5-7.5).

Water hardness should be kept between 2 to 20 dGH.

Temperature control is another important factor in maintaining good water quality, as fluctuations in temperature can stress out your fish and make them more susceptible to disease.

A reliable heater with a thermostat should keep the temperature between 72°F-79°F, which is optimal for these freshwater fish.

Common Diseases

You may feel worried about the health of your beloved iridescent shark, as they can be susceptible to various diseases that could harm their well-being and shorten their lifespan.

It’s essential to watch for any symptoms of illness and take prompt action to prevent further damage.

Here are some common diseases that your iridescent shark might face:

  • Ich – a parasitic disease that causes white spots on the body
  • Fin rot – a bacterial infection that causes the fins to deteriorate
  • Swim bladder disease – a condition where the fish struggles to maintain balance in the water

Symptom identification is crucial in diagnosing and treating these diseases promptly.

Treatment options like medication, water changes, and isolation can help cure these illnesses.

However, prevention measures such as maintaining good water quality, feeding high-quality food, and avoiding overcrowding are vital in keeping your iridescent shark healthy and happy for years.

If you notice any concerning symptoms in your fish, consult a veterinarian or experienced aquarist for guidance on proper treatment methods and medications.

Diet and Feeding

Feeding an iridescent shark a diverse diet that includes live food can ensure they receive all the necessary micronutrients for optimal health and longevity.

Although they aren’t picky eaters and can thrive on a flake-based diet, it’s important to supplement their diet with live food options.

Live food options such as bloodworms, brine shrimp, worms, and feeder fish contain essential vitamins and minerals that cannot be found in dry food alone.

Regarding feeding habits, iridescent sharks should be fed in small amounts multiple times throughout the day instead of one large meal.

This helps prevent overfeeding and ensures they can access fresh food throughout the day.

It’s also important to monitor their nutrient requirements and adjust their diet as they age.

By providing a varied diet with dry and live foods and monitoring feeding frequency, owners can help ensure their iridescent shark stays healthy and happy for years.

Behavior and Temperament


Are you looking for a peaceful addition to your aquarium? Consider adding a school of iridescent sharks, as they’re known for their calm and non-aggressive behavior.

These fish are social creatures that thrive in groups, so it’s important to keep at least 4 of them together.

When kept alone or with aggressive tank mates, iridescent sharks can become stressed and display signs of aggression.

Providing environmental enrichment in their tank is essential to ensure the best group dynamics and minimize any potential aggression triggers.

Adding driftwood, rocks, and other hiding places will give them spaces to explore and create territories within the group.

It’s also important to note that these fish may become more active during feeding, but this behavior is not a sign of aggression.

Proper care and attention make a school of iridescent sharks an enjoyable addition to any community tank.

Compatible Tank Mates

Peaceful and shy iridescent sharks should be kept away from aggressive fish.

When deciding on a tank mate for your iridescent shark, it’s best to choose a peaceful fish of a similar size.

Anything much smaller may be considered an easy meal, which you want to avoid. Make sure to pick a compatible friend for your shark that won’t be mistaken for dinner!

While small aggressive fish may not be as much of a threat, it’s still best to steer clear.

If you’re looking for suitable tank mates for your iridescent sharks, here are some recommendations: Bichir, Oscar fish, Silver dollar fish, large plecos, Black shark, and Tinfoil barbs. All of these species should get along swimmingly with your iridescent sharks.

The importance of keeping iridescent sharks in a school cannot be overstated.

They’re social creatures and do much better when kept with others of their kind.

Keeping them alone can cause stress and negatively impact their health and lifespan.

The Importance Of A School

Creating a school of iridescent sharks in your aquarium promotes their comfort and well-being and enhances these unique freshwater fish’s beauty and natural behavior.

As schooling fish, iridescent sharks thrive in groups and feel more secure when surrounded by others of their kind.

Here are some benefits of schooling:

  • Social behavior: By grouping, iridescent sharks engage in social interactions such as swimming, playing games, and grooming each other.
  • Stress reduction: Being alone can cause stress for these fish, and having friends around can help alleviate this stress and promote better overall health.
  • Group dynamics: In a school, one dominant individual usually leads the group, and this hierarchy helps to maintain order and prevent aggression among members.
  • Improved aesthetics: A school of iridescent sharks swimming together creates a beautiful sight in your aquarium that will impress guests.
  • Natural behavior: In the wild, these fish swim in schools, and keeping them alone or with incompatible tank mates removes their natural behavior.

Overall, keeping a school of at least 4 iridescent sharks is highly recommended to provide them with an environment encourages good health and happiness.

They’ll thrive when they have companionship and space to swim around freely.

Breeding Tips

To successfully breed these magnificent creatures, you must create a separate breeding tank and replicate their natural habitat with appropriate plants, rocks, and driftwood.

Breeding iridescent sharks in a home aquarium is not feasible due to its challenges.

These fish require a lot of space for swimming and schooling, making it difficult to provide adequate breeding conditions in a typical home setup.

Additionally, iridescent sharks have complex reproductive behavior that requires specific environmental cues for successful mating.

Genetic diversity is also important for healthy offspring, which can be challenging when breeding within a limited home environment.

While aquaculture potential exists for iridescent shark breeding, it’s best left to experienced professionals with the resources and expertise to provide optimal conditions for successful reproduction.


Raising iridescent sharks in a home aquarium can be a rewarding experience for any fish enthusiast.

However, it’s important to remember that these fish require a significant commitment regarding tank size and maintenance.

From providing adequate space to ensuring proper feeding habits, there are many factors to consider when caring for iridescent sharks.

That being said, with the right care and attention, iridescent sharks can thrive in a home aquarium and provide endless enjoyment.

Whether you’re a seasoned aquarium owner or just starting, learning about these beautiful fish can help ensure their health and happiness for years.