Here is a link on how to care for them:
http://www.petco.com/caresheets/fish/Arowana.pdf
Behavior
Osteoglossids are
carnivorous, often being specialized surface feeders. They are excellent jumpers; it has been reported that
Osteoglossum species have been seen leaping more than 6 feet (almost 2 metres) from the water surface to pick off insects and birds from overhanging branches in South America, hence the nickname "water monkeys". Arowana species typically grow to around 2 to 3 feet in captivity.
Several species of osteoglossid exhibit extensive parental care. They build nests and protect the young after they hatch. All species are
mouthbrooders, the parents holding sometimes hundreds of eggs in their mouths. The young may make several tentative trips outside the parent's mouth to investigate the surroundings before leaving permanently.These fishes are best kept with live or frozen feed and they easily outgrow the tank within a span of 8-10 months. Always preferred in a large type aquarium of at least 150 gallons.
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[edit] In the aquarium
Arowanas are solitary fish and only appreciate company while young; adults may show excessive dominance and aggression. Some compatible fish often partnered with this fish are
clown knifefish,
pacu,
oscars,
plecostomus,
jaguar cichlids,
green terrors,
gar, siamese tigerfish (
datnioides microlepis) and any other semi-aggressive fish that cannot fit in the arowana's mouth.
Australian species are best kept singular in aquaria.
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