Care
The Silver Arowana is widely distributed throughout the Amazon River basin in Brazil, Colombia, Ecuador, and Peru, and is also found in the Oyapock River in French Guiana and the Rupununi River in Guyana. Here, this predatory surface-dweller prefers heavily vegetated, sluggish waters, including creeks, oxbow lakes, streams, and swampy lagoons, usually lurking in areas with floating plant cover or overhanging branches and feeding on a variety of creatures, including small fishes, crustaceans, frogs, terrestrial and aquatic insects, along with some plant matter. A voluminous aquarium with powerful filtration to match is required if you wish to keep this large, solitary fish. The length and width of the tank is generally much more important than the height, providing as much surface area as possible, allowing for the arowana to turn freely. The aquarium must be biologically mature before adding this species. Decor is not critical, and would mainly be included for the benefit of large, robust fish living at lower levels which may prefer some shelter. Much more important for the arowana would be maximum swimming space and attention to water quality. The Silver Arowana is a voracious eater that produces a lot of waste, and requires continuous excellent water conditions if it is to be free of health problems such as eye and gill issues. To this end, filtration must be powerful and the water well-oxygenated. A frequent partial water change regime is absolutely essential as substandard conditions can lead to the aforementioned ailments. Several huge canister filters can be employed, but sump filtration may be more prudent as then equipment such as heaters can be kept in the sump and out of the main tank where they would be very easily damaged. The Silver Arowana is belligerent and highly territorial with its own kind, so should only ever be kept singly in an aquarium. Tankmates must be chosen with care, as arowanas have deceptively capacious mouths and will eat any fish small enough to swallow. Most arowanas will tolerate large, robust companions that occupy the lower levels, such as big armoured catfish, large characins and cyprinids, sizeable cichlids, or stingrays. However, always introduce all intended tankmates first, the arowana being the very last addition, as otherwise it can be extremely territorial when introducing new fish into what it perceives as its established domain. It is essential that the aquarium has tight fitting coverslides as these fish are expert jumpers; an adult specimen will be heavy, so ensure the lid is weighted down. ***This fish is a huge commitment in terms of housing, equipment, maintenance, and longevity. Much consideration needs to be given prior to purchase to ensure its needs can be met.***
Feeding
Offer a varied selection of meaty foods. Smaller specimens will take bloodworm, Mysis shrimp, chopped seafood etc. Larger specimens will enjoy earthworms, prawns, cockles, mussels, crab, crayfish etc. Some will also take pellet foods, but this is very much trial and error.
Breeding
This species has not been bred in the home aquarium. It is a paternal mouthbrooder that is bred in large numbers on a commercial basis in Southeast Asia. The male fish holds the eggs/fry (which typically number 12-30) in his mouth for around 6 weeks. The fry are quite sizeable on hatching, and possess a huge yolk sac from which they initially gain nutrition.
