Jardini Arowana (Scleropages jardinii): A Guide to Care and Compatibility

The Jardini Arowana, also known as the Australian Arowana or Gulf Saratoga, is a unique and striking freshwater fish with shimmering scales and a predatory nature that fascinates aquarists. Native to Northern Australia and parts of New Guinea, this species belongs to the Osteoglossidae family and is highly sought-after for its elegance and charisma in home aquariums. Here’s a comprehensive guide to the Jardini Arowana, its origin, aquarium requirements, and suitable tank mates.

Origin and Natural Habitat

Scientific Name: Scleropages jardinii
Place of Origin: Northern Australia, Papua New Guinea, primarily in river systems like the Jardine River (hence the name) and areas of the Gulf of Carpentaria.

Jardini Arowanas are usually found in slow-moving rivers, billabongs, and floodplains where vegetation and structure provide ample hiding spots. In the wild, they are ambush predators, using their excellent vision and agility to capture prey near the water's surface. Unlike the Asian Arowana, they’re better suited for a home aquarium setting due to their manageable size.

Physical Characteristics and Behavior

The Jardini Arowana typically grows up to 24-30 inches in captivity, though they can reach even larger sizes in the wild. Known for its silver-gray scales with pinkish or gold spots, the Jardini has a streamlined, elongated body and a slight dorsal fin that complements its graceful movements. Its aggressive temperament and territorial instincts make it a more challenging fish to house with others, but it’s highly rewarding for experienced aquarists.

Setting Up the Aquarium

To keep a Jardini Arowana happy and healthy, it's essential to replicate its natural environment as closely as possible. Here are some setup recommendations:

• Tank Size: A minimum of 180 gallons is recommended for a single adult Jardini Arowana. They require ample swimming space, so an aquarium with a length of at least 6 feet is ideal.
• Water Parameters: Jardini Arowanas thrive in warm, soft, and slightly acidic to neutral water.
  • Temperature: 75–82°F (24–28°C)
  • pH: 6.5–7.5
  • Water Hardness: 3–12 dGH
• Filtration and Water Flow: Arowanas are sensitive to water quality, so a high-quality filtration system is necessary. The filter should have a moderate to strong output, but avoid creating strong currents, as Jardinis prefer gentle water flow.
• Decorations and Substrate: Use a sand or gravel substrate with minimal decorations, as these fish are known to move about quickly, and large objects can cause injury. Adding some driftwood and floating plants can create shade and help them feel more secure.

Diet and Feeding

In the wild, Jardini Arowanas are carnivorous, feeding on insects, crustaceans, and smaller fish. In captivity, a varied diet is best:

• Primary Diet: High-quality pellets designed for carnivorous fish or arowanas.
• Supplements: Feeder fish, crickets, mealworms, shrimp, and occasional treats like frozen fish or earthworms.
• Feeding Frequency: Feed juveniles twice daily, while adults do well with one feeding per day.

Tank Mates for Jardini Arowana

Selecting tank mates for Jardini Arowanas can be challenging due to their aggressive and territorial nature. It’s best to avoid smaller fish or any that could be seen as food. Opt for sturdy, similarly sized, or larger species that can tolerate the Jardini’s temperament:

1. Large Cichlids - Species like Oscars, Flowerhorns, and Green Terrors can often hold their own and thrive in a similar water environment.
2. Bichirs - Polypterus species are hardy and can cohabitate well with Jardinis due to their resilience and bottom-dwelling habits.
3. Large Catfish - Species like the Redtail Catfish or Plecos can work, as they generally stay out of the Arowana’s way at the bottom of the tank.
4. Other Large Fish - Silver Dollars or Tinfoil Barbs can sometimes be successful, as they’re swift and move in schools, which can help mitigate aggression.

When introducing tank mates, always monitor closely for signs of aggression. Avoid housing multiple Jardini Arowanas together, as they tend to be extremely territorial toward conspecifics.

Common Challenges in Keeping Jardini Arowanas

• Aggression: Jardinis can become aggressive toward other fish, especially when cramped or feeling territorial. A spacious tank can alleviate this somewhat, but their aggressive tendencies may still persist.
• Jumping: Jardini Arowanas are known for their jumping ability, so a tightly sealed tank lid is essential to prevent injuries.
• Water Quality Sensitivity: Regular water changes and monitoring are necessary to maintain a pristine environment.

Conclusion

The Jardini Arowana is a captivating fish, suitable for advanced aquarists ready for the challenge of keeping such a majestic species. With the proper setup, diet, and care, a Jardini can thrive and display its beautiful colors and unique personality. Though aggressive, their tank mate compatibility isn’t impossible with careful selection and monitoring. For aquarists who love predatory fish and have the space, the Jardini Arowana is a rewarding choice that adds a bold, captivating presence to any large aquarium.