Silver Arowana: Ultimate Guide (Care, Diet, Breeding, & More)

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Written By Matt Stevens

Hi, I'm Matt! I've been obsessed with fishkeeping for over 15 years now and created this site to share my knowledge with others.

The Silver Arowana is a beautiful and majestic freshwater species that are highly sought after in the aquarium community.

However, caring for these species isn’t for beginners, and even experienced aquarists tend to be scared of them.

People who have raised and bred several challenging species of fish before will be able to rise up to the task and care for them in their home aquarium, but not recommended for complete beginners!

If you want to learn about how to care for Silver Arowana, then we are here to help. This guide has been designed to teach you everything you need to know about caring for these fish, their habitat, water requirements, diet, tank mates, breeding process, and much more!

Species Overview

The Silver Arowana belongs to the family of Osteoglossidae, and they are known by the scientific name Osteoglossumbicirrhosum. They are highly popular and are also considered to be the ultimate fish for aquarium owners to take care of.

Although they have a beautiful and captivating appearance, they can be really difficult to take care of.

Life Span10 to 15Years
Color FormSilver
Care LevelDifficult
SizeUp to 36 inches
Tank SetupFreshwater: rocky and vegetative
Minimum Tank Size250 Gallons

These fish are native to the Amazon River Basin in South America. You might also see them being referred to as Dragonfish or Monkey fish. They are known to be quite aggressive and have predatory instincts.

In fact, they even look intimidating, so you will have to think twice before deciding if you want to raise them. This is why beginners should refrain from keeping them in their aquarium. Apart from their behavior, they also have a strict care regimen, diet, and water requirements.


Silver Arowanas are known to live quite long and have an average lifespan of 10-15 years. This means that they are a long-term investment and a huge responsibility for aquarists.

Just like other fish and invertebrates, their lifespan is also affected by factors like water conditions, diet, and habitat. Even the slightest changes can hinder their growth significantly.

Therefore, you have to be on your toes and keep monitoring the conditions inside the tank regularly.


Silver Arowanas have long and slender bodies, which leads them to being classified among “band fishes”, a term used to group different species with similar body shapes. Once you take a look at them, you will see why they are called this.

Their body structure is much different from other types of fish. Their size starts reducing gradually towards the tailfin, and they look flatter if you look at them from the side. However, their front view shows them to be quite thick.

They also have a small tailfin, and their anal and dorsal fins stretch all the way towards it. At first glance, you would think that their fins are connected, but this isn’t the case.

These fish also have thin pelvic and pectoral fins, along with two distinguishable barbels that protrude from the tip of the mouth. This is why they are sometimes known as Dragonfish.

Another striking feature of their appearance is their mouth, which has a diagonal position and opens up like a drawbridge. The shape of their mouth helps them devour their prey within seconds.

These Arowana have a silvery appearance, hence their name. Their bodies have large and pearlescent scales, whereas the babies have a bluish hue on their scales.

Generally, you won’t be able to tell apart the male and female fish, but the females are slightly thicker, while the males have a longer anal fin.


The Silver Arowana is big, and they normally achieve a length of 36 inches when fully grown, even in an aquarium. In their natural habitat, they can grow up to a length of 48 inches.

Their large size is one of the biggest hurdles that aquarists have to overcome when they decide to keep these fish in their home aquarium. You may also think that you can keep them in a smaller tank for now and get a bigger one when they start growing.

However, Arowana can grow 2-3 inches every month, which means that you won’t have a lot of time to get a new tank. Plus, it would be tedious and time-consuming to transfer all the species into a new tank, so you should get a large tank beforehand.

Silver Arowana Care

As you may have gauged already, caring for Silver Arowana isn’t an easy feat, particularly due to their size and aggressive temperament. Plus, they are highly sensitive to changes in water conditions.

To ensure that they thrive in captivity, you need to replicate their natural habitat and also keep the water conditions maintained. Let’s have a look at all of the requirements that you need to fulfill in order to care for these fish.

Tank Size

Since these fish are big in size, the minimum tank size you need to keep them should be 250 gallons, especially if you are raising adult fish. If you have juveniles, they can thrive in a 60-gallon tank as well. However, they grow by 2 inches every month, which means that soon you will have to get a new tank.

Ideally, they should be allowed to start off in larger tanks, so that they have ample space to move around, and can also feel at home in their aquarium.

If you fail to provide them with a suitable and large habitat, they will start to feel suffocated and stressed, and this would dial-up their aggressive temperament. Some aquarists have also reported that they tend to jump out of the tank when they start to feel claustrophobic.

Moreover, being stuffed into a smaller tank can also prevent these fish from growing to their full size, and also develop deformities and diseases that would greatly shorten their lifespan.

Water Parameters

Silver Arowanas are used to living in warm streams and water bodies that flow into rivers throughout South America, and they are known to thrive in both whitewater and blackwater conditions.

This doesn’t mean that you have to replicate the blackwater conditions and actually make the water look stained. However, you need to pay close attention to the water temperature, hardness, and pH levels to keep them healthy and happy.

Generally, the Amazon River Basin has warm waters with slightly higher acidity. Although these fish are resilient and flexible, you shouldn’t experiment with their water conditions too much.

To keep your Silver Arowana happy, you should maintain the water temperature between 75°F and 82°F, whereas the pH levels should be between 5.0 and 7.5. Lastly, you should aim for a water hardness between 1 and 8 dKH.

As mentioned above, it is incredibly important to monitor the water conditions from time to time. To make it easier, you should equip yourself with an aquarium testing kit and use it every 2-3 days to check the water.

What to Put in Their Tank?

Since Silver Arowanas are native to the Amazon River Basin, they prefer lots of vegetation and rocks. However, they prioritize having lots of space to swim around easily. Because they have large-sized bodies, they need a lot of room, which means that you shouldn’t add too many plants to the tank.

Ideally, you should place a few plants at the back of the tank, preferably plants with strong roots. This is because these fish can easily dig up plants. The middle portion of the tank should be left empty for the fish to swim around.

The aquarium should have a fine gravel substrate, and you can put the plants inside it. Apart from this, you can also add rocks and driftwood to serve as hiding places for the fish. Although they are quite intimidating, they like to have hiding spots handy when they feel nervous or stressed.

Another thing you need to think about is strong filtration since Silver Arowanas are quite sensitive to water changes. For this purpose, you should invest in a top-quality and efficient filter in order to keep the ammonia and nitrate levels in check.

Along with this, you should also change the water by 25% every week to bring down the ammonia and nitrate levels, which can be harmful to your fish.

Last but not least, you need to top off the aquarium with a lid, because these fish are known to jump as high as 3 meters, especially when they are stressed or intimidated. If you don’t cover the tank and you see them escape, try to put them back quickly.

Generally, you will find these fish near the surface of the water, and they are actively searching for prey.

Common Diseases

The Silver Arowana is susceptible to various diseases that are common with freshwater species, such as Ich or white spot disease. Apart from this, they can also suffer from a host of bacterial and parasitic infections, which include fin rot, Dropsy, etc.

Fin rot is a freshwater disease that causes the tissues of the fins to become frail and discolored, and it also makes the fish vulnerable to additional infections. Dropsy is a lung infection that affects juvenile fish, and it causes their bodies to swell up.

Apart from these, you also have to be careful about not placing any sharp objects or accessories in the tank, since they are prone to physical injuries. While swimming around the aquarium, they damage their barbels and also cut their bodies on sharp edges and surfaces.

Last but not least, these fish are more likely to become ill if they suffer from stress, which can be caused due to a small tank, overcrowding, and also poor water conditions.

Therefore, you should make sure that these conditions and requirements are fulfilled so that your fish don’t suffer from any kind of disease.

What Do Silver Arowanas Eat?

Thankfully, feeding Silver Arowanas isn’t as big a challenge as other things are. Since they are natural carnivores, they are used to eating whatever they can find in the wild, including plant-based and animal-based food.

They prey on small creatures in the wild, including small fish, insects, crustaceans, frogs, and much more. Their massive size and drawbridge-like mouths allow them to easily devour their prey quickly.

In the tank, you can feed them with both live and frozen foods, including feeder fish, crab, crickets, and shrimp. To nourish them with protein, you can feed them brine shrimp, bloodworms, earthworms, and other tiny creatures.

Although some experienced aquarists have fed them with dried pellets, others advise against it.

Behavior & Temperament

The Silver Arowana is known to be the most intimidating and predatory in the aquarium community, and they will overpower and eat any fish that can fit into their mouth.

However, when they aren’t actively searching for prey, they can be quite nervous and frisky. They are also mindful of their surroundings, and will also start moving around when you get closer to the tank, shuffling off to find a hiding spot.

After some time, they will get used to you visiting the tank, but it is unwise to keep their tank at a place where a lot of people pass through or stand to watch them because they will be continuously stressed this way.

Silver Arowana Tank Mates

If you think caring for Silver Arowana is tough, wait till you search tank mates for them. These fish don’t even do well with their own kind unless you provide them with a huge tank where each fish can easily mark their own territory.

Since they are quite aggressive, putting too many of them in a tank would only invite trouble and excessive fighting. Moreover, putting peaceful fish with them is also a no-no, because they will gobble them up within seconds.

If you do want a multi-species aquarium, you should ensure that it is large enough to house different species that cohabitate with the Silver Arowana.

Ideally, you can select similar-sized fish that have an aggressive temperament, so that they can protect themselves and can’t be eaten easily.

Here are some suitable tank mates for your Arowana:

As you can see, the emphasis is on larger fish that are more aggressive, so that they don’t attack or get attacked by your fish. Moreover, if you have a large enough tank, these species will mind their own business and won’t bother your fish.

Whenever you place a new fish into the tank with Silver Arowanas, make sure to keep an eye on them for the first few minutes, and keep checking back to see if they are getting along. If not, you should be prepared to separate them from each other in order to avoid fighting.


When it comes to their breeding process, you can pretty much forget about it in an aquarium, due to the aggressive and predatory nature of these fish. Moreover, Silver Arowanas are very particular about mating and do it in the flood season in the wild.

Since they don’t get along well with each other, it can also be difficult for you to find a pair that is ready to mate and breed.

Nevertheless, the breeding process is quite interesting, even if you don’t see it happening in the tank. The male and female fish will build a nest, and the female will lay eggs inside it. Once she is done, the male takes them in his mouth – not for eating, but to keep them safe until they hatch.

Silver Arowana are what you call ‘mouthbrooders’ i.e. fish who keep the eggs in their mouth and nurture them until the fry are ready to hatch. The male has to do this for up to 50 days until the eggs hatch, and 5 additional weeks until the fry are ready to swim in the aquarium and scavenge for food.

By this time, the fry are already quite large, and they can eat feeder fish and brine shrimp easily.

Final Thoughts

By now, you may be either fascinated or intimidated by Silver Arowanas, especially knowing how strict and particular their care regimen is. It isn’t impossible but can be quite difficult and requires dedication.

If you think you can easily manage a large-sized tank and also maintain the particular conditions required by these fish to stay healthy and happy, we encourage you to go for it.

After all, you have our guide to follow if you ever get stuck!