Iridescent Shark (Pangasianodon Hypophthalmus)
The Iridescent Shark, also known as the Iridescent Catfish or Sutchi Catfish, is a large freshwater fish that requires a spacious tank and a dedicated aquarist. These fish are known for their unique dorsal fin that resembles a sail, and their dark, shiny skin that transitions to a solid grey as they age. With their large eyes and long barbels, these fish are a sight to behold in any aquarium.
Iridescent Sharks are native to Southeast Asia's deep and wide rivers, particularly the Mekong and Chao Phraya Rivers. They are known to migrate significant distances during different times of the year. In the aquarium, these fish require a large tank of at least 300 gallons to accommodate their size, which can reach 3-4 feet in length and live up to 20 years in optimal conditions.
Iridescent Sharks are peaceful and shy shoaling fish that feels more secure in groups. However, housing multiple individuals would require a significantly large tank.
Iridescent Sharks are peaceful fish and can coexist with other large and peaceful species such as catfish, plecos, large cichlids, and other peaceful fish of similar size. Aggressive fish should be avoided as tank mates, as Iridescent Sharks are not equipped to defend themselves. While the Iridescent Shark is not an aggressive species, its large size means it may unintentionally consume much smaller tankmates. Its constant activity can also disturb more sedate or timid fish, but it can be easily intimidated by aggressive or boisterous species. Ideal companions are large, peaceful bottom-dwelling and mid to upper-water shoaling species, such as Doradids like Oxydoras niger, Megalodoras urunoscopus, or Pterodoras granulosus, as well as Pacu or many larger cyprinids.
These fish are omnivores and appreciate a varied diet. A high-quality flake-based diet, supplemented with frozen or live foods such as bloodworms, brine shrimp, worms, and occasional vegetables, will keep your Iridescent Shark healthy and happy.
While adult Iridescent Sharks do not require specific decor if the tank lighting is dim, you may add large pieces of bogwood, beech branches, or smooth rocks. Ensure any decor is either too heavy to be moved or is securely attached, and that there's plenty of open swimming space. This species is very active and tends to become nervous in confined spaces, which can lead to injuries from colliding with the tank glass or decor.
As a riverine species, it prefers well-oxygenated, flowing water. A large and efficient biological filter is necessary to manage the waste produced by a fish of this size. A sump-type filter is recommended, as it allows most of the equipment to be located outside the tank, preventing damage from a large specimen. The tank should also be fitted with a heavy cover, as the Iridescent Shark may occasionally breach the surface during bouts of nervous behavior.
The care for these fish is straightforward, with the main challenge being their size. Regular monitoring of water conditions is essential, as these fish are sensitive to changes in water parameters. They thrive in water temperatures of 72°F to 79°F, pH levels of 6.5 to 7.5, and water hardness of 2 to 20 dGH.
It's important to note that Iridescent Sharks are not suitable for every aquarist due to their size and specific care requirements. However, for those who are prepared to provide the necessary care and environment, owning an Iridescent Shark can be a rewarding experience.
To learn more about this fish, be sure to check out the Additional Information tab.