Expanded Fish Care

Silver Arowana

Kingdom: Animalia

Phylum: Chordata

Class: Actinopterygii

Order: Osteoglossiformes

Family: Osteoglossidae

Genus: Osteoglossum

Species: Osteoglossum bicirrhosum

Note- I have kept my Silver Arowana with a couple of tank mates, a Black Feather Fish Knife Fish, and Common Pleco. 

Care level-Experienced  

Temperament and Behavior- Easily Startled and jumps often. You will have to get used to the sound of water splashing with this species. It's not uncommon for you to hear splashing sounds of various intensities throughout the day. Aggressive to any other fish species that will fit in their mouth, if the other fish will fit in their mouth it will be quickly eaten.  

Lifespan- 10-15 years in captivity 

Size- Possibility to grow three feet+

Diet- I feed all kinds of foods one or two times a day. Veggie Rounds, Hirikri, Frozen Blood Worms, Frozen Brine Shrimp, Crickets, Mealworms, Earthworms, Grasshoppers, and Minnows. 

Feeding time is honestly one of my favorite times for bonding with my Silver Arowana. The jawline is one of their distinguishing factors. Their chin and mouth open upward to capture food and the species family classification suggests Osteoglossidae (bony tongue). Having teeth on their tongue, jaw, and the upper part of the mouth pharynx helps them succeed as a predatory species. 

Minimum Tank Size- I initially found my Silver Arowana in a ten-gallon tank at the local fish store. I could only keep my Silver Arowana in a 20-long aquarium for a short time before needing an upgrade to a 55-gallon tank. However, just a short time later, I purchased a 180-gallon aquarium, my Silver Arowana's current home, and will outgrow this tank quickly. MUST HAVE AN EXTREMELY LARGE AQUARIUM.

pH- 6.5-7.5

Water Hardness- I keep my Silver Arowana in Harder Water. 

Temperature-75-80 degrees Fahrenheit

Tank-mates- I recommend introducing your Silver Arowana and a chosen tank-mate(s) when they are on the younger side. If already mature, make sure the tank-mate is large enough to not fit in the Silver Arowana's mouth. Also, try to choose a less aggressive fish that spends more time in the tank's mid to lower level since Arowana spends most of the time at the surface. Mine will swim to the bottom for missed food but will spend most of the time at the top. The only tank mates were a Black Feather Finned Knife Fish and a large Common Pleco.

Recommended Group Size- ONE

One of the most challenging parts of keeping this fish species, I find, is how fast they do grow. They have a big, big appetite and rapid growth. I recommend having a larger tank set up and cycled before purchasing a Silver Arowana. Finding a large tank reasonably priced on short notice is extremely difficult.

My Silver Arowana jumps often, and if deciding to purchase, proceed with caution. You will regularly hear water sounds from them jumping. Lost scales and minor scrapes do happen. 

Tank Setup- When caring for a Silver Arowana and their aquarium setup, the most critical aspect is that this fish species is a monster fish. They will grow to a large size in a short period and require a large environment. My Silver Arowana is currently in a 180-gallon tank and is two feet long. 180-gallon is probably the smallest size tank I would recommend. However, this aquarium needs to be upgraded to an eight-foot aquarium soon (220-gallon).  

This aquarium is heated with an Eheim Thermocontrol Heater and set for 78 degrees Fahrenheit, with no decorations. This species jumps often and can land on large decorations or driftwood pieces and easily cause injury. The last thing you want to happen is to injure the backbone. My Silver Arowana does uproot live plants along with the Common Pleco. I use a mix of Fluval Stratum and black aquarium sand for substrate. This aquarium does require more significant filtration, and this 180-gallon tank has a Fluval FX-4 canister filter. The only decoration is a large cave on the bottom, which serves as a secure place for the Common Pleco. 

Issues- I have only had minor injuries due to jumping leading to scratches and a few lost scales. Again, I have not added decorations to the aquarium. Suppose the Silver Arowana lands on decor that could break the backbone.

Drop-eye does seem to affect Silver Arowana in the home aquarium, including my own. I do not know what causes drop-eye and if severe surgery can correct it.