Silver Arowana: Species Profile

The Silver Arowana (Osteoglossum bicirrhosum) is a captivating freshwater fish renowned for its sleek, metallic appearance and distinctive hunting behavior. Originating from the Amazon Basin in South America, this species is a favorite among experienced aquarists due to its impressive size and unique characteristics.

Species Overview

• Common Names: Silver Arowana, Dragon Fish, Monkey Fish
• Scientific Name: Osteoglossum bicirrhosum
• Adult Size: Up to 36 inches (90 cm) in captivity; larger in the wild
• Life Expectancy: 10 to 15 years

Characteristics

• Family: Osteoglossidae
• Origin: Amazon Basin, South America
• Social: Solitary; can be aggressive towards smaller fish
• Tank Level: Top
• Minimum Tank Size: 250 gallons
• Diet: Carnivore
• Breeding: Mouthbrooder; challenging in captivity
• Care Level: Advanced
• pH: 6.0 to 7.5
• Hardness: 1 to 8 dGH
• Temperature: 75–86°F (24–30°C)

Origin and Distribution

Silver Arowanas are native to the slow-moving rivers, floodplains, and swamps of the Amazon Basin in South America. They thrive in warm, soft, and slightly acidic waters rich in vegetation, providing ample cover and hunting grounds.

Colors and Markings

This species is characterized by its elongated, streamlined body covered in large, silver scales that reflect light, giving it a metallic sheen. The dorsal and anal fins extend towards the tail, creating a sleek profile. Juveniles may exhibit a bluish tint, which fades as they mature.

Tankmates

Due to their predatory nature and potential size, Silver Arowanas are best kept alone or with other large, robust fish that can coexist without being perceived as prey. Suitable tankmates include:

• Large catfish species
• Bichirs
• Large cichlids

It’s crucial to monitor interactions closely and provide ample space to reduce territorial disputes.

Habitat and Care

To replicate their natural habitat:

• Tank Setup: Provide a spacious aquarium with a secure, heavy lid, as Silver Arowanas are known to jump. Incorporate sturdy driftwood and large rocks to create hiding spots, but ensure ample open swimming space.
• Water Parameters: Maintain stable water conditions within the recommended pH and hardness ranges. Regular water changes and efficient filtration are essential to keep the environment clean and healthy.
• Lighting: Moderate lighting is preferred, which can help showcase their metallic coloration without causing stress.

Diet and Feeding

Silver Arowanas are carnivorous predators with a preference for live prey. A balanced diet includes:

• Live or frozen foods such as shrimp, crickets, and mealworms
• Occasional feeder fish, ensuring they are disease-free
• High-quality carnivorous pellets

Feed them once or twice daily, offering only what they can consume within a few minutes to prevent overfeeding and maintain water quality.

Gender Differences

Determining gender in Silver Arowanas can be challenging, as males and females exhibit similar external features. Subtle differences may include males having a slightly longer anal fin and a more slender body, but these distinctions are not always reliable.

Breeding

Breeding Silver Arowanas in captivity is challenging and requires specific conditions:

• Breeding Tank: A large, secluded tank with optimal water parameters is essential.
• Spawning: After courtship, the female lays eggs, which the male fertilizes and then carries in his mouth for incubation.
• Raising Fry: Once the fry are released, they can be fed small live foods like brine shrimp. Providing a separate rearing tank can increase survival rates.

Further Research

For those interested in similar species, consider exploring:

• Black Arowana (Osteoglossum ferreirai)
• Asian Arowana (Scleropages formosus)
• Jardini Arowana (Scleropages jardinii)

These species share comparable care requirements but may exhibit differences in temperament and appearance.

FAQ

• How large of a tank is needed for a Silver Arowana? A minimum of 250 gallons is recommended to accommodate their size and activity level.
• Are Silver Arowanas suitable for beginners? Due to their size, specific care requirements, and potential aggression, they are best suited for experienced aquarists.
• Can Silver Arowanas live with other fish? While possible, it’s challenging. Tankmates must be large and robust, and even then, compatibility is not guaranteed.

By providing appropriate care and a suitable environment, Silver Arowanas can be a stunning and rewarding addition to a large freshwater aquarium.