Pearl Arowana (Scleropages jardinii), Jardini Arowana or Australian Bonytongue 5"

The Pearl Arowana (Scleropages jardinii), also known as the Jardini Arowana or Australian Bonytongue, is a large, predatory freshwater fish native to Northern Australia and New Guinea. It is highly prized by experienced aquarists for its majestic, ancient appearance, metallic iridescent scales, and powerful swimming style.

Overview of the Pearl Arowana

Scientific Name: Scleropages jardinii.

Maximum Size: Up to 24 inches (60 cm) in captivity.

Lifespan: Typically 10 to 20 years with proper care.

Temperament: Highly aggressive and fiercely territorial.

Care Level: Advanced (not recommended for beginners).

Aquarium & Tank Setup

Pearl Arowanas grow very fast and require a massive amount of physical space to turn around comfortably.

Tank Size: Minimum 250 gallons for an adult fish.

Tank Shape: Length and width are much more important than tank height.

Security: A heavy, tightly fitted lid is mandatory because they are elite jumpers.

Decor: Use heavy driftwood and smooth rocks. Leave the upper tank mostly open for swimming space. Avoid fragile, rooted plants as they will likely be uprooted.

Water Parameters

Arowanas produce large amounts of waste. You must invest in a powerful filtration system and perform frequent water changes to keep the water pristine.

Temperature: 75°F to 82°F (24°C to 28°C).

pH Level: 6.0 to 7.5 (slightly acidic to neutral).

Hardness: Up to 15 dH (prefers relatively soft water).

Diet & Feeding

These fish are strict surface-dwelling carnivores. They prefer meaty foods that float or stay near the top of the water column.

Juveniles: Feed high-quality bloodworms, Mysis shrimp, and small pieces of chopped fish.

Adults: Feed earthworms, whole prawns, crickets, gut-loaded insects, mussels, and krill.

Pellets: Carnivore floating pellets can be introduced early, though some individuals can be stubborn to accept them.

Compatibility & Aggression

The Jardini/Pearl Arowana is notorious for being one of the most aggressive Arowana species.

Solitary Housing: It is highly recommended to keep this fish completely alone in a species-only display.

Tank Mates: Coexistence is very difficult. If attempted, choose large, bottom-dwelling fish like Plecos, Bichirs, or large Freshwater Stingrays.

What to Avoid: Never keep them with other Arowanas or any fish small enough to fit into their mouths.