Arowana

Arowana

Arowanas are freshwater bony fish of the family Osteoglossidae, also known as bonytongues^[1] (the latter name is now often reserved for Arapaimidae).^[2] In this family of fish, the head is bony and the elongated body is covered by large, heavy scales, with a mosaic pattern of canals. The dorsal and anal fins have soft rays and are long based, while the pectoral and ventral fins are small. The name "bonytongues" is derived from a toothed bone on the floor of the mouth, the "tongue", equipped with teeth that bite against teeth on the roof of the mouth. The arowana is a facultative air breather and can obtain oxygen from air by sucking it into its swim bladder, which is lined with capillaries like lung tissue.^[3]

Evolution

Osteoglossids are basal (primitive) fish from the lower Tertiary and are placed in the actinopterygiid order Osteoglossiformes. As traditionally defined, the family includes several extant species from South America, one from Africa, several from Asia, and two fromAustralia.^[1] Today Arapaimidae is often regarded as a separate family, which includes the arapaimas and the African arowana.^[2]Consequently, the South American genus Osteoglossum, and the Asian and Australian genus Scleropages are the only extant genera that remain in the osteoglossid family.^[4] Arapaimidae and Osteoglossidae split about 220 million years ago (Mya), during the Late Triassic.^[5]

Within Osteoglossidae, the South America Osteoglossum arowanas diverged from the Asian and Australian Scleropages arowanas about 170 Mya, during the Middle Jurassic.

The Osteoglossidae are the only exclusively freshwater fish family found on both sides of the Wallace Line.^[6] This may be explained by the theory that Asian arowanas (S. formosus) diverged from the Australian Scleropages, S. jardinii and S. leichardti, about 140 Mya, making it likely that Asian arowanas were carried to Asia on the Indian subcontinent.^[7][5]

Fossil record

At least five extinct genera, known only from fossils, are classified as osteoglossids; these date back at least as far as the Late Cretaceous. Other fossils from as far back as theLate Jurassic or Early Cretaceous are widely considered to belong to the arowana superorder Osteoglossomorpha. Osteoglossomorph fossils have been found on all continents except Antarctica.^[8] These fossil genera include Brychaetus, Joffrichthys, and Phareodus.

Behavior

Osteoglossids are carnivorous, often being specialized surface feeders. They are excellent jumpers; Osteoglossum species have been seen leaping more than 6 ft (almost 2 m) 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 ft in captivity.

Several species of osteoglossids exhibit parental care. They build nests and protect their 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.

Arowana Feeding info

Arowana prefer live food or at the very least floating food. They will not generally eat from the bottom of the tank. To this end keeping your arowana with a suitable bottom feeder may be a good idea to prevent the buildup of detritus in the tank.

Appropriate foods can range from:

Mealworms, crickets, grasshoppers, locus, garden worms, fly, small frogs, small fish, shrimps, beef heart, etc.

The food your arowana will like is very personal to the fish, so try lots of different things and see how they respond.

Some food help to promote colour in your fish. Any food that contains ceratanoids will help develop red and gold colouring in your fish. However, it is recommended to always maintain a varied diet in your fish.

You can also feed live food on material high in ceratanoids, i.e feed carrots or shrimp to mealworms and then the mealworms to the Arowana.

Feeding patterns effect both the size and colour of your Arowana. Overfeeding can make the fish grow faster but can adversely affect both the colour and the long term health of the fish. Since the size, colour and health is very important do not regularly overfeed any Arowana.

For small fish feeding once or twice a day until they lose interest is enough. From six to 12 inches, once per day is enough. Beyond 12 inches you can consider once every two days, or even less.

High protein foods are also often low in nutrients. Food such as Mealworms are similar to crisps for humans. They taste great but do not have high nutritional value, they provide ideal variety but are a poor stable food.

The best food is fresh fish from your local fish market cut into cubes. You may have to starve the fish for up to several weeks in order to train them to eat food that is not live. If you feed live fish then make sure they are properly quarantined and disinfected before feeding them to your Arowana. Other fish are generally more susceptible to parasites which can in turn damage or kill your Arowana.

Natural Habitat & Lifestyle

Most species of Arowanas are home to the flood plains of South America. These fish are maybe one of the most unique looking fish of the freshwater habitat. It’s not uncommon for them to grow up to 46 inches long in their natural habitat. The flood plains of South America can contain very shallow water depths and the Arowana can actually survive out of the water for some time. It’s unique swim bladder allows it to still breath completely out of the water while possibly moving to a different body of water.

Aros are found naturally in white and black water floodplains of South America in the freshwaters of theAMAZON River Basin and River, maybe in the Rupununi andOyapock Rivers, and in some still waters of Guyana as well.

What is mind blowing about this fish is the fact that they have been seen jumping as far as 6 feet into the air for their prey. If you have seen how fast they strike the water surface to indulge their prey.. you can imagine how scary they look shooting out of the water to strike their next meal. Not to mention how scary they already look. They are commonly referred to as “prehistoric looking” and I agree.

Different Species & Types

Some of the species of Aros that are available have been manipulated by man to produce new species. Some types are so rare that they are costing hundreds of thousands of dollars to have these as pets in fish aquariums. Breeders are always on the lookout for rare breeds just for the mere fact of breeding them toMAKE MORE MONEY with selling their babies. Click here to view an article on all the species and types.

Pet Arowanas in Fish Aquariums

They are commonly hanging around the top of fish aquariums waiting to strike. In natural lifestyle, Aros jump out of the water to catch insects hanging on low hanging trees. It’s an incredible site to see but a nightmare for fish aquarium owners. Nobody wants their exotic pet fish jumping out of the tank and laying on the floor. Keep tops over your tanks for safety (refer to tank setup portion).

*Note: Remember that different species are going to be different in cost. Some are very rare and exotic. Some of the more common species are the Silver and Red Aro.

When setting up your aquarium for an Arowana, you will need good filtration. These fish are very messy because of their strong eating habits. Keep a close eye on your water parameters because the can change very fast with this style of a fish. Have a scheduled time every week in which you do water changes.

Figure out what percent works good for your tank and how often to do them. Most fish keepers that own “Aros” already know these basics because this fish is more of an intermediate level aquarium fish. It’s good to educate new hobbyists on what needs to happen to keep clean water parameters though. Also note that these fish take lots offoods rich in protein and that will also effect your clean water when they attach the food.

Price to Buy Arowana for a Pet

Depending on what species of Arowana you desire to have as a pet will determine how much it is going to cost you. Because some species are on the endangered species list, the cost is going to be extremely high if not even illegal to have as a pet. For more common species of Arowanas, the prices are going to very from $50 to a couple hundred dollars per fish. What usually makes these more common species more expensive is size of the fish. Fish keepers desire a larger fish because they are more beautiful and it takes a long time to get to a large size growth.

Size of Fish Aquarium Needed?

These fish aren’t for beginner level aquarium owners. When fish grow to be as large as Aros do, you need very large fish aquariums. I would advise nothing smaller than 100 gallons of aquarium space. You may be able to get away with a smaller aquarium when the fish is in juvenile state, but they do grow at a rapid pace and it’s almost not even worth your time. Most Aro enthusiasts have 125 gallon aquariums and larger.

If your new to the hobby, you will quickly find that keeping pet fish like this is very expensive. A 125 gallon aquarium can commonly cost around $500 U.S. dollars. So to say the least, keeping these fish is a very serious setup. Most beginners are turned down when they research what it takes in cost just to keep these fish.