Jardini Arowana Aquarium Care, Feeding and Native Habitat Information
Native Habitat and Species Information
Indigenous to the Jardine and Adelaide Rivers of northern Australia, Jardini Arowana can be found from still billabongs to flowing streams. They are large, highly evolved, powerful predators and can be traced back millions of years without many changes (earning them the title, "living fossil"). Jardini Arowana are also known as Gulf Saratoga, and like their South American cousins, they are sometimes referred to as "water-monkeys" due to their unique predatory behavior where they will hide, stalk, and jump out of the water to ambush insects and small animals that are just passing by or hanging out on an overhanging branch or nearby vegetation. Jardini Arowana are usually not too hard to obtain from local fish stores, but are harder to find than their Silver Arowana cousins. Although they are considered to be more elusive in the wild, they are becoming more popular in the hobby due to captive breeding programs. Jardini Arowana are a very fun fish to keep and can offer a lot of enjoyment for the advanced to expert hobbyist. They are constantly on the move, swimming around the aquarium (just under the surface) with plenty of activity. They are a true "bony tongue" species that is long and flat, with large eyes (offering them great hunting accuracy), a dark, silver-gray, stream-lined body with seven rows of large scales that tend to have pink to orange hued edges, and fins that are a darker, metallic coloration with various pink to orange spotting. As evolved predators, Silver Arowana have large, oblique mouths lined with small, sharp teeth rooted in their oral bones which include their jaws, tongue, pharynx and palate; they also possess forked barbels on the tip of their bottom jaw used for sensing disturbances on the water surface. Males have a longer anal fin and can be distinguished by their prognathous jaws, where females are usually thicker when fully mature.
Jardini Arowana require an aquarium of at least 180 gallons with a sand or gravel substrate and should also be provided with driftwood (tannins in the driftwood will help maintain a lower pH) and vegetation; it's a good idea to have some free-floating plants or plants that will adhere to driftwood as some individuals do not tolerate rooted vegetation. They will also require a secure, enclosed top on their aquarium as they are powerful and notorious jumpers. Weekly 15-25% water changes should be carried out (frequency can vary depending on aquarium filtration efficiency) as Jardini Arowana are very sensitive to water chemstry. Although they can be easily bullied by larger Cichlids when they are young, once Jardini Arowana hit the 8 to 12 inch mark, they usually become extremely aggressive to all other tank inhabitants, especially those of a similar shape; tank mates should be chosen very carefully. Jardini Arowana are a solitary, aggressive, territorial species, but have, on occasion, been known to coexist with large Oscars, large Manguense, large, predatory catfish, and large plecos, but it's hit or miss and more often than not, they are eventually the only fish left in the aquarium. The Osteoglossidae family arguably contains the hardiest freshwater fish species', which don't often get sick, although they grow to be large and become messy eaters and can eventually develop health problems if their water chemistry is not properly maintained.
Feeding & Nutrition
Jardini Arowana are carnivores and should be provided with a variety of meaty and vitamin enriched foods such as live, frozen or freeze-dried ghost shrimp, krill, minnows, bloodworms, blackworms, mealworms, earthworms, crickets, frogs, crayfish, and Cichlid/Arowana pellets or sticks.
Jardini Arowana are mouth brooding, egg-layers and aquarium breeding is extremely difficult, but not impossible (a large tank of 600+ gallons would be needed). In the wild, spawning commences at the start of the wet season, where they will pair off and lay their eggs (50-200). Once fertilized, the female will keep the eggs in her mouth until they hatch. When the fry hatch they will stay with their mother for around 4-5 weeks and threatened the mother will open her mouth allowing the young to seek shelter.