A massive, prehistoric-looking surface predator native to the Amazon Basin. Known for their metallic silver scales and incredible jumping ability (used in the wild to catch insects from low-hanging branches). They grow exceptionally fast and require gigantic aquariums. They will consume any tank mate small enough to fit into their large, trapdoor-like mouths.
At a Glance
Tank Requirements
Water Parameters
Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Standard (Adult)
The fully mature form. Requires an extraordinarily large tank (minimum 8 feet long) with a heavily weighted, secure lid due to their explosive jumping capability. Generally peaceful with fish too large to eat, but fiercely territorial against other Arowanas.
Same care requirements as the base species
Also known as: Adult Arowana, Full Grown Arowana
Juvenile (Grow-out)
Baby Arowanas often sold with their yolk sacs just absorbed. They grow astonishingly fast (often 1-2 inches per month). While they can temporarily be housed in smaller aquariums, they will require an 8-foot tank within their first year to prevent stunting and 'drop-eye'.
Differs in 4 traits from base species
Also known as: Baby Arowana, Fingerling, Juvenile
Albino / Platinum (Adult)
A highly sought-after color morph lacking normal pigmentation. Care, sizing, and extreme tank requirements are identical to the standard Silver Arowana.
Same care requirements as the base species
Also known as: Albino Arowana, Platinum Arowana, Snow White
Silver Arowana Care Summary
The Silver Arowana, scientifically known as Osteoglossum bicirrhosum, belongs to the Oddballs family group. Adults reach a maximum size of approximately 100 cm and have a compressed body shape with a fast growth rate. Classified as semi-aggressive, this species primarily occupies the surface zone of the aquarium and produces a extreme level of biological waste.
To thrive, the Silver Arowana requires a freshwater only aquarium with a minimum volume of 1000 litres and a tank length of at least 240 cm. Water temperature should be maintained between 24°C and 30°C, with a pH range of 6–7.5 and a general hardness of 1–12 dGH. A moderate water flow is preferred. To replicate their natural habitat, the tank should include smooth gravel (sensitive barbels).
Only one Silver Arowana should be kept per aquarium. Keepers should be aware that this species will prey on fish small enough to fit in its mouth, will defend a territory within the tank, and is a known jumper, so a tight-fitting lid is essential. This species is available in 3 varieties: Standard (Adult), Juvenile (Grow-out), and Albino / Platinum (Adult). Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Similar Species
Pictus Catfish
Pimelodus pictus
An extremely active, striking silver catfish with black spots and incredibly long barbels, native to South America. While peaceful toward similarly sized tank mates, they are highly effective nocturnal predators that will easily swallow small fish (like Neon Tetras) whole. They are scaleless and possess sharp pectoral spines that can easily become entangled in aquarium nets.
Black Ghost Knifefish
Apteronotus albifrons
A fascinating nocturnal predator native to the Amazon basin. It lacks a dorsal fin and moves via a continuous undulating ventral fin, allowing it to swim backwards as easily as forwards. It generates a weak electrical field to navigate and hunt in the dark. Scaleless and highly sensitive to medications, it requires smooth hiding places (like PVC pipes or smooth driftwood). Will consume any fish small enough to fit in its surprisingly large mouth.
Clown Knifefish
Chitala ornata
A massive, nocturnal predator native to Southeast Asia, widely known for the distinct row of ocellated spots above its anal fin. While sold as small silvery cute juveniles, they grow incredibly fast into nearly 1-meter giants that require immense aquariums. They are obligate carnivores and will eat any fish small enough to fit in their large mouths. They are shy during the day and require large hiding tubes or caves.
Red-Tail Catfish
Phractocephalus hemioliopterus
A massive, fast-growing predatory catfish from the Amazon basin. Famous for its voracious appetite, bulldozer-like behavior, and distinct red caudal fin. Due to its enormous adult size (often exceeding 4 feet), it is strictly a 'monster fish' that requires a heated indoor pond or a colossal custom aquarium. It is highly predatory and will swallow absolutely any tank mate that can fit into its cavernous mouth.
Freshwater Angelfish
Pterophyllum scalare
The most iconic South American Cichlid, known for its distinct arrowhead shape and majestic fins. While domestic strains are hardy, they remain cichlids: they are semi-aggressive predators that will eat any fish small enough to fit in their mouths (like Neon Tetras). They form loose shoals as juveniles but pair off and become territorial as they mature. Height is more important than length for this species.
Amano Shrimp
Caridina multidentata
A highly popular, industrious freshwater shrimp renowned for its unmatched algae-eating abilities. Popularized by aquascaper Takashi Amano, they are significantly larger and hardier than most dwarf shrimp (like Cherry Shrimp). They are notorious food-thieves during feeding time and excellent escape artists, requiring a tight-fitting lid. Their larvae require saltwater to develop, so they will not overpopulate in a freshwater aquarium.