Species Overview
Scleropages jardinii — the Jardini or pearl arowana — is native to northern Australia and southern New Guinea. It reaches 24 inches in captivity, smaller than other arowanas but stockier and more powerful per inch.
Distinctive features: pearl-like spots on body and fins, deeper body shape, heavily armored scales. Color is olive-green to bronze with iridescent spots.
Aggression — The Defining Trait
Jardinis are the most aggressive arowana species. They will attack mirror reflections, tank mates of any size, and even hands during cleaning. Solo housing is the only reliable approach.
Pairs in 500+ gallon tanks sometimes work if introduced as juveniles, but expect ongoing fin damage and the occasional fatal fight. Most experienced keepers maintain Jardinis alone.
Tank Setup
Minimum 180 gallons (6 ft length) for an adult Jardini. Bare-bottom or dark sand. Heavy filtration. Sturdy weighted lid — Jardinis jump even more aggressively than silvers when startled.
Avoid décor with sharp edges. Jardinis bash into walls and rocks during territorial displays.
Diet
Jardinis are voracious predators. Floating pellets (Hikari Massivore), crickets, large shrimp, and earthworms make a balanced diet. Feed adults every 2 days; juveniles every day.
Watch for bloat. Jardinis will eat until physically unable to swim. Feed measured portions.
Water and Health
Jardinis tolerate harder water than other arowanas (pH 6.8–8.0 acceptable) but prefer 78–84°F. Weekly 30% water changes, nitrate under 30 ppm.
Common issues: fin tears from self-aggression on tank glass, eye injuries from collisions, internal parasites in wild-caught specimens.