The Iridescent Shark Resource

Iridescent Shark

Iridescent Shark“Iridescent Shark” is the common name for the Pangasianodon hpophthalmus species.

Adult size: 3ft
Minimum tank size: 300 gallon
pH: 6.5-7.5
Temperature: 72-79°F (22-26°C)
Decor: Rocks, Driftwood, and Plants
Substrate: Any
Lighting: 8-10 hrs/day
Diet: Omnivore

How To Keep Iridescent Sharks
How To Breed Iridescent Sharks
Other Information About Iridescent Sharks


How to Keep Iridescent Sharks


If you adopt Iridescent Sharks from a contaminated source, your aquarium may become infected. As a result, you need to ensure you only adopt ones that are kept in a healthy environment.

They can be adopted from:

Before adopting them, understand:

  • Iridescent Sharks have an average life expectancy of 12-15 years.
  • Iridescent Sharks may be identified under the common names of: Siamese Shark, Asian Shark Catfish, Shark Catfish, Tiger Shark, Striped Catfish, Pangasius Catfish and Sutchi Catfish.

Tank Requirements

Tank Size & Population Density

If your Iridescent Sharks are in an aquarium that is overstocked, they will become stressed – weakening their immune systems – causing them to be more prone to diseases, and they won’t grow to their appropriate size. As a result, you need to follow the rule of one inch of fish per gallon of water, but keep in mind:

  • Iridescent Sharks must be kept in at least a 75 gallon aquarium for the first year of their life. As they approach their adult size, they must be kept in at least a 300 gallon aquarium.
  • Iridescent Sharks eventually grow to be 2-3 feet long.

How do I setup a fish tank? (Opens new tab)
How do I determine the size of my aquarium? (Opens new tab)

Canopy & Lighting

The canopy of your aquarium ensures:

  • Your fish don’t jump out of your aquarium.
  • No contaminates enter your aquarium.

As a result, equip your aquarium with a canopy that completely covers it.

As far as lighting goes, if you want your Iridescent Sharks to be most comfortable, the amount of light they get needs to mimic the amount of sunlight they receive in their natural habitat. The amount of time you should leave their aquarium’s lights on to achieve this varies. If it’s in a room that doesn’t get a lot of sunlight, you should turn their lights on during sunlight hours. However, if it’s is in a well-lit room, then 2-3 hours per day is all that is necessary.

Decor & Substrate

When keeping Iridescent Sharks, they will thrive if you decorate their aquarium with decor and substrate that mimics their natural habitat.

The natural decor for them consists mainly of driftwood, river rocks, and plants, so you should add plenty of them to their aquarium. When arranging these things though, you need to ensure you:

When arranging these things though, you need to ensure you:

  • Place the decors so that it provides them with plenty of open swimming areas.
  • Place the decor in a fashion that allows you to see them – don’t create a barrier for them to hide behind.

Both gravel or sand is a suitable option for them. In either case, you need to ensure you:

  • Clean their substrate beforehand. Otherwise, the residue that is on it will make their aquarium cloudy.
  • Fill their aquarium with at least 2 inches of substrate.

Water Parameters

If the water in your Iridescent Sharks’ aquarium doesn’t reflect that of their natural habitat, they can become stressed – weakening their immune systems – causing them to be more prone to diseases. As a result, you need to ensure their aquarium has a pH level of 6.5-7.5 and a temperature of 72-79°F (22-26°C).

• pH
pH can be measured by using a Freshwater Master Test Kit. If you measure your water’s pH level and it needs to be altered: remove your fish, adjust the pH, then acclimate your fish back into your aquarium – since they are sensitive to drastic changes of pH.

• Temperature
To measure your aquarium’s water temperature, equip your aquarium with an aquarium thermometer.

Ammonia, Nitrites, & Nitrates

The subject of Ammonia, Nitrites, and Nitrates tends to be very dry. In its simplest form, they are all a byproduct of fish waste (fish poop & uneaten food) and are toxic to Iridescent Sharks. As a result, you need to ensure their aquarium has:

  • An Ammonia concentration of 0-0.2 mg/L.
  • A Nitrite concentration of 0-0.2 mg/L.
  • A Nitrate concentration of 0-20 mg/L.

If you need to test these concentrations, use a Freshwater Master Test Kit.

If you need to reduce these concentrations, ensure proper:


Iridescent Sharks are omnivores, so their diet regimen should consist of meats and vegetables.

They should be fed twice per day – for a total of 14 feedings per week. For a majority of the feedings, they should be fed a staple food consisting of either flakes or pellets. For the other feedings, they should be fed special foods.

In the early to mid-part of their life, they require lots of meats so that they get the necessary proteins for growth. As they grow older, they will lose their teeth and become more herbivorous. During each feeding, they should be fed as much food as they can eat in 4-6 minutes. The exact foods they should be fed varies, depending on their size:

Of course, this is just our feeding method. You are more than welcome to design your own diet regimen for your Iridescent Sharks. In either case though, ensure you:

Health Issues

Iridescent Sharks are most-commonly affected by Ich or Malawi Bloat.

Tank Mates

Iridescent Sharks are compatible with one another. If you do keep them together, it is best to keep them in a group of 4-5 to help spread out the aggression.

As far as keeping them with other species goes, just make sure you do not keep them with any fish that is small enough to fit in their mouth, otherwise they will be eaten. If you want to know for sure though, use this Compatibility Chart to ensure they are compatible with them.


How to Breed Iridescent Sharks

Due to their large size and strange breeding behavior, Iridescent Sharks have not been successful bred in captivity.


Other Information About Iridescent Sharks


Iridescent Sharks are native to the Mekong basin, Chao Phraya River, and Maeklong basin. Although they are actually catfish, it is their shark-like appearance that has made them popular among fishkeepers.

Conservation Status

The Conservation Status of Iridescent Sharks was most recently published in 2006 as Endangered, according to the IUCN.

Taxonomic Status

The Taxonomic Status of Iridescent Sharks was most recently published in 1878 by Henri Émile Sauvage as:

Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Siluriformes
Family: Pangasiidae
Genus: Pangasianodon
Species: P. hypophthalmus


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