Arowana’s (also known as dragon fish) are awesome monsters fish, that don’t only look the part, they act the part.
And providing optimal care is key to seeing them flourish. In this guide, you’ll learn exactly how to do that.
Table of Contents
In the Wild: Arowana Overview
Arowanas are a species of fish that are part of the ancient family of osteoglossidae.
This group of fish are sometimes (rather strangely) called “bony tongues” because of a toothed plate of bone that they have on the lower part of their mouth.
Inhabiting the inland waters of South America, Southeast Asia, and Australia, these fish have elongated bodies covered with large scales and a distinct pair of barbells protruding from the tip of their lower jaw.
Sounds handsome, huh?
Because of their looks, arowanas are also sometimes known (especially in Asian countries) as “dragon fish” or “shui long” in Mandarin.
Folklore tells us that arowanas bring luck, since they resemble a traditional Chinese dragon. They’re highly predatory fish that you’ll often see elegantly patrolling the surface of the water.
And get this:
Arowanas can live over twenty years in captivity. That’s more than most domesticated dogs! There have even been unconfirmed reports of arowanas living to nearly FIFTY years.
With that in mind, there’s no denying that keeping an arowana is a long-term commitment.
Probably the most sought-after and popular freshwater monster fish in the world, the arowana even makes an appearance in literature and is cited as “the world’s most coveted fish” in the book The Dragon Behind the Glass by Emily Voigt.
Types of Arowanas
While there are only 6 species of ‘true’ Arowanas, there are plenty of geographical and naturally occurring variants as well.
Here, we’ll discuss in detail almost each and every kind Arowana:
South American Arowana
Let’s go through some that originate from South America.
Silver Arowana (Osteoglossum bicirrhosum)
The silver arowana (osteoglossum bicirrhosum) is the largest of of all the arowana species, capable of growing to 3 and a half feet in length- wowza!
While it is the biggest arowana, it’s also known to be one of the most docile as well.
It has a distinct metallic silver color and elongated dorsal and anal fins, which only the arowanas from South America have. Lastly, it’s the most common and least expensive arowana you can find.
Pro Tip: A Silver Arowana (osteoglossum bicirrhosum) can easily reach 16”-20” in length within the first year.
Black Arowana (Osteoglossum ferreirai)
Black arowanas closely resemble the silver arowana in both shape and size. As juveniles, black arowanas have a distinct black band covering the length of their body.
However, as they mature, this band slowly disappears, leaving their body with a slight tint of purple, which is most prominent towards their anal fin (ooh la la).
Compared to the silver arowana, they grow considerably slower and also have a more slender body.
Let’s go through those from Australia.
Australian Arowana (Scleropages jardinii)
Native to both Australia and South Central New Guinea, the Australian arowana is one of two species of arowanas that come from this region.
Their body is covered in copper colored scales accented with small pink edges, which sometimes appear as pink spots on the fins. Similar to its silver sibling, the Australian arowana has the potential to grow to almost 3 feet in length.
Most consider the Australian arowana to be the “bad boy” of the arowana world due to their tendency to wear leather jackets and drive fast motorcycles fiery temperament.
Because of this, keeping Aussie arowanas in a tank with others can be a real challenge. While some have certainly succeeded in keeping them in communities, most Australian arowanas won’t tolerate tank mates once they reach 12-14 inches in size.
Saratoga (Scleropages leichardti)
The saratoga lives within the Fitzroy River in East Central Queensland, Australia.
These lil’ guys are probably the least-known arowana species and are usually only kept by hardcore arowana fanatics (I see you, dudes!).
They closely resemble the Australian arowana in both size and appearance.
However, the pink coloration towards the edge of the scales is way more prominent and widespread with the saratoga; not to mention the fact that they’re also a bit more slender than the Australian arowana (so not fat shaming you, Aussie arowana- you know we love you!!).
In contrast, the pair of barbels protruding towards the edge of saratoga’s lower jaw are extremely short compared to other arowanas.
Now onto the Asian arowanas.
Green Arowana (Scleropages formosus)
You’ll find the green arowana living at the Nami Dam in Malaysia. Colloquially known as the Asian arowana, it has a pale gray coloration with a slight tint of green- especially towards the edge of its fins.
This Asian arowana has shorter dorsal and anal fins than South American arowanas and can grow up to around 3 feet in length.
Banjar / Yellow Tail Arowana (Scleropages formosus)
The Banjar arowana is native to Banjarmasin, Borneo. This particular species is pretty distinct, in that its dorsal, caudal (tail), and anal fins are yellow while the rest of its body has a yellowish/greenish tint.
Red Tail Golden Arowana (Scleropages formosus)
The red tail golden arowanas (also known as RTGs) can be found within the Siak River system in Pekanbaru, Indonesia.
Considered the ‘classic’ look for Asian arowanas, the red tail golden arowana is one of the most sought after of any arowana species.
And no wonder, since it looks so striking:
It has deep red fins with golden scales covering more than half of its body. But RTGs are different from all the other arowanas in that their beautiful golden scales (which experts refer to as the shine) will never grow past the fourth row of scales from their belly.
The scales without shine are usually a dull dark gray color.
Golden Arowana (Scleropages formosus)
Probably the most famous Asian arowana of all, the golden arowana is one of the most coveted ornamental fish around the world. For real, yo!
Native to Bukit Merah in Indonesia, the golden arowana is special because its shine extends all the way up to the sixth row of scales.
Golden arowanas who have shine like this are known as ‘crossbacks’, because the level of shine has crossed up to their back (erm… obviously).
A golden arowana that has a fully golden head as well as the crossback coloration is known as the elusive ‘golden head full helmet crossback’, and is the most expensive and prestigious type of golden arowana.
When it comes to this Asian arowana, the more intense the gold coloration is, the more desirable they are to aquatic hobbyists.
There are also special variants of the golden arowanas that have a tint of blue towards the latter half of their bodies. These are called ‘blue-based crossbacks’ and are also considered premium fish.
Pro Tip: You can occasionally find a special kind of arowana which is a hybrid of the RTG and crossback, known as high back red tail golden arowanas (HBRTG).
Red Arowana (Scleropages formosus)
The majestic red arowana naturally occurs in the waters of Lake Sentarum in Kalimantan, Borneo.
Hobbyists reckon it’s one of the most expensive ornamental fish in the world and has even eclipsed its rival, the golden arowana, when it comes to popularity and value. Take that, golden arowana! Burrrrrrn!
As the name suggests, the red arowana is colored red from barbell to tail.
But here’s the thing:
As juveniles, this coloration will only be prominent towards the lips and the fins. Yet as they mature, that red color begins to spread all over their bodies.
At around 3 years old, the red coloration on its scales will be very prominent (as long as you’ve given it proper care and a good diet up till then).
Red arowanas are fiercely sought after, thanks to their gorgeous red color and unique appearance.
But even more than that:
Its distinct red color and similarities to a dragon is reminiscent of the common Asian symbols for luck and prosperity. The superstitious among us might believe that a red arowana would bring luck and prosperity to its owner.
Pro Tip: Buyers beware! If you hear of a super red, blood red, or chilli red arowana, don’t be fooled! These are merely your standard red arowanas being marketed under gimmicky names to increase their value.
Batik Arowana (Scleropages inscriptus)
The Batik arowana originates from Myanmar and closely resembles the green arowana in both color and looks.
But the batik arowana is a special fella:
It has very distinct scribble markings all over its body; markings which are said to resemble the tribal war tattoos of ancient Polynesian civilizations.
Because of this, the batik arowana is becoming more and more popular amongst aquatic hobbyists.
Onto the African arowana.
African Arowana (Heterotis niloticus)
The African Arowana can be found in tons of locations around Africa, specifically within the Chad and Nile rivers.
And how about this:
It grows up to almost 4 whopping feet in length!
In reality, it’s actually a much closer relative of the arapaima rather than the arowana. However, due to its relatively small size compared to its giant cousin, it’s much more commonly thought of as an arowana.
Its appearance is different from any other arowana we’ve discussed so far. It has a distinct round head and a downward pointing mouth- and there’s a very good reason for this.
African arowanas are sand-sifters. They feed by sifting through sand for crustaceans and other molluscs.
Their body is elongated with fins and scales similar to South American Arowanas. They’re usually dark green with yellow/pale brown bellies.
Variants of Arowana
While these variants are mainly genetic conditions that may occur in all species of animals, the following are mostly seen with the S. Formosus and the O. Bicirrhosum species of arowana:
Albinism is caused by a genetic condition causing the lack of pigmentation throughout the body of the fish. All albino fish have very light yellow to white bodies with red eyes.
Albino arowanas are very rare and extremely expensive.
Albino Asian arowanas (say that three times fast, I dare ya!) are worth a staggering tens of thousands of dollars, while albino silver arowanas are worth “just” hundreds of dollars.
The term platinum is loosely used in the fish keeping hobby for those that are leucistic, meaning they have a genetic condition which causes partial loss of pigmentation throughout the body.
In turn, it causes an animal to be pale or matte-white in color while retaining the original coloration of its eyes.
Platinum Asian arowanas have been sold around the world for- wait for it… half a million dollars! Meanwhile, platinum silver arowanas (which are also known as snow arowanas) are worth thousands as well.
Setting up your Dragon’s Den (Arowana Tank)
Now we’re going to go through what you need to do to set up your Arowana tank.
What kind of Tank do you Need and What Size?
The first thing you should consider when setting up a tank for an arowana is the size of the tank.
Here’s a few golden rules to keep in mind:
Arowana is a monster fish. As such, it should only follow that a monster fish needs a monster tank.
The absolute minimum tank size for a solitary arowana (with possibly a few tank mates) is:
220 gallons (6’ x 2.5’ x 2’) for a South American arowana
120 gallons (4’ x 2’ x 2’) for an Asian or Australian arowana
You must also put special consideration toward the width of the tank, because even when the fish grows longer than the tank is wide, they’re still dexterous enough to turn around if given ample space.
Then there’s the tank glass:
Glass thickness for tanks must never be compromised. Arowanas are powerful enough to break glass that’s less than half an inch thick (yikes!).
Due to the sheer size and weight of these tanks, only a very sturdy stand should also be used. And since tanks that big are not easily movable, I’d advise that you carefully plan where you’ll be placing your tank(s) before actually purchasing them and setting them up.
Pro Tip: Always keep your tanks in spacious places where there is an easily accessible good water source, drain, and where added humidity will not be an issue.
Also, having a sturdy tank lid with no gaps is a MUST!
Just by looking at the position of the mouth of an arowana, you’ll be able to see that it’s a surface feeder; and in the wild, arowanas are known to actually jump right out of the water to take down insects and other prey- Rambo style!
They can- and they will- jump out of the tank if given the opportunity to do so.
So spare yourself the calamity of skating around your sitting room floor chasing after a rogue arowana, and make sure that a lid or cover is always in place.
Pro Tip: Use a mesh cover with holes small enough for the arowana’s fins not to get tangled, yet flexible enough not to cause bump traumas.
What Kind of Substrate is Best for Arowana?
The choice of whether or not to use a substrate is a matter of preference for arowana keepers.
It could either increase or decrease the contrast of colors within your tank, which in turn either enhances or diminishes the natural beauty of your arowana.
I’d recommend that you veer away from substrate since such tanks are generally harder to clean. Likewise, having substrate may lead to organic waste building up and causing problems in the long run.
Do I Need Plants and Decorations
More often than not, plants and decorations are not necessary for arowanas, since the fish themselves could very well serve as the decoration.
They’re just that darn beautiful.
Moreover, plants and decorations are not really ideal because the sheer size of these fish means that they’re going to need all the space they can get. Plus, sharp decorations can also end up causing injury to your fish.
If you really want to, you can always choose to place some floating plants in the tank to deter the arowanas from jumping out (just keep in mind that having plants alone will not stop your arowana from jumping outside of the tank. Remember the lid thing!).
What Lighting Do I Need?
Lighting is essential when it comes to maximizing the beauty of your arowana. There are two kinds of lighting fixtures you’ll want to look at before purchasing your first arowana:
First is the viewing light, which is a key piece of kit for every species of arowana.
Second, is the tanning light which is often used to intensify the colors specifically on gold or red arowanas. For red arowanas, some prefer to use pink or purple lights to really accent the red color.
While the topic of using tanning lights being humane or not is always up for debate, it’s a widely accepted truth that the use of these lights does indeed enhance the natural coloration of both the gold and red arowanas.
If you really want to maximize the coloration of your gold or red arowana to its utmost potential, then I would advise you to use tanning lights.
This is because a red arowana, without proper grooming and care, would only be orange colored at best- leading some hobbyists to feel disappointed with their fish.
Pro Tip: Direct sunlight also helps improve fish coloration.
For viewing lights, all species of arowanas prefer having a nice light over them, since they’re sight feeders without any other special abilities to detect prey.
I’d recommend that you use LED energy saving lights that are tailored specifically for the type of arowana you have- especially if you’re keeping the red and/or golden arowana. LEDs are very powerful, efficient, and last longer than other kind of lights.
Pro Tip: Suddenly turning on viewing lights may spook arowanas and cause them to jump. It’s best to have an ambient room light open before actually turning the viewing lights on.
Ideal Water Parameters for Arowana
Water parameters should be monitored regularly by using commercially available water test kits.
As a rule of thumb:
Ammonia (NH4): Should be kept at absolutely 0 ppm
Nitrites (NO3): Should be kept at absolutely 0 ppm
Nitrates (NO4): Should be kept below 40 ppm
In terms of temperature:
Arowanas are tropical fish, so they should be kept in water around 30° Celsius (or 86° Fahrenheit). However, Australian arowanas are known to be able to thrive in cooler temperatures.
As for the water hardness:
Most arowanas are already bred in captive, so they’re able to tolerate a wider range of water hardness. However, they do best with water hardness levels of 6.0-7.0 Ph.
Pro Tip: Arowanas tend to display a more vivid coloration if the water is a bit more acidic.
How Much Filtration do Arowana Need?
Newsflash: big fish produce big waste!
Arowanas need to consume high-protein food to cope with their rapid growth- and to satisfy their big appetites.
Because of this, they also produce large amounts of waste that could easily pollute your tank’s waters if the filtration system is not up for the job.
While there are a lot of conventional filtration systems available in pet shops around the world, you should only use very efficient and powerful filtration systems for arowanas.
Arowanas are thought of as ‘the holy grail of the tropical fish’ by aquatic hobbyists, so perhaps it should follow that only the best filtration system(s) should be used.
The key component for an arowana-proof filtration system is that it must be able to contain and sustain a lot of ‘biological media’, so as to be able to cope with the large amount of waste these monsters produce.
Here are the top 3 of the best filtration systems to use for arowanas:
A Sump filter is an added ‘sump’ tank that holds your filtration media.
It adds another tank designed to circulate your tank’s water towards chambers filled with both biological and mechanical filtration media.
It’s one of the best filtration systems available.
Relatively small compared to the sump filter, canister filters pressure water from the tank towards the compact filtration system and through the many layers of media within it.
Canister filters are designed to maximize both space and efficiency; just make sure that the canister filter you get is rated for the size of the tank you have.
Trickle filters have layer over layer of plastic filtration boxes stacked on top of each other and sitting above your tank.
A pump pushes water through a spray bar pipe which then causes water to trickle over the filtration media within the boxes. This also saves you a lot of space while being able to utilize a large amount of filtration media.
Pro Tip: Make sure you use good quality filtration media so as to maximize the amount of beneficial bacteria living inside them.
A Special Word on The Nitrogen Cycle
To be able to understand why our water parameters and filtration systems are so important, it’s a good idea to look at the nitrogen cycle.
You must also keep in mind that the by-products of this process are toxic and can be lethal to your fish- and should therefore be closely monitored and curbed.
In a nutshell:
The nitrogen cycle is nature’s way of breaking down organic waste. Once your fish produces waste (or uneaten food decomposes) it turns into ammonia (NH4). Ammonia is very toxic to your fish and can easily cause burns- and even death.
But don’t freak out:
Thankfully, there’s a good bacteria called nitrosomonas which can live and propagate within your biological filtration media, working to break down ammonia and turn it to nitrites (NO3).
Though you ain’t off the hook just yet:
Nitrites are also very toxic for your fish, which is why we need our biological media to house and help propagate another good bacteria called nitrobacter. In turn, nitrobacter breaks down nitrites into the less toxic nitrates (NO4).
While nitrates (NO4) are known to be less toxic than ammonia and nitrite, prolonged exposure to high levels of nitrates could still be detrimental to the health of our fish.
At this point, I know what you must be thinking:
Does it ever end?!
The answer is yes, my arowana loving friends. The answer lies in levels. Let me explain:
The level of nitrates a fish will be able to tolerate and stay healthy is below 40 ppm.
The level of nitrates can be lowered and controlled simply by doing consistent water changes. Adding plants also help lower nitrates.
Pro Tip: Prolonged exposure to high amounts of nitrates could cause a fish’s growth to be stunted.
To sum it all up:
Because these byproducts are toxic to our fish, we want our ammonia and nitrite levels to be absolutely ZERO and our nitrate level to be below 40 ppm at all times.
We could achieve this by having a lot of beneficial bacterium (nitrosomonas and nitrobacter) living and thriving within the biological medias of our filtration system and performing regular water changes.
This is precisely the reason why our filtration system should be efficient and able to house a lot of biological filter media. Consistency is king with regard to water parameters.
If you’re a tad confused, don’t worry. I have this big easy-to-follow guide on performing the Nitrogen Cycle.
Pro Tip: The bacterium nitrosomonas and nitrobacter thrive very well in waters with high oxygen content, so don’t forget to have a lot of surface agitation through aeration.
Diet Requirements and Feeding Arowana
Arowanas are carnivores. In the wild, they prey on small fish and insects- both in and out of the water- and due to their large size and rapid growth, arowanas need a high protein quality diet.
What to Feed my Arowana?
As juveniles, arowanas will readily accept small live fish and other small insects such as worms, roaches and crickets.
You should always consider the size of the prey you will be offering to your fish.
As they grow, you could slowly wean them to accepting non-live frozen foods such as market shrimp, prawns, shellfish, and other meal fish.
Although it’s not easy to achieve, there are some arowanas who would eventually take processed food such as pellets.
However, you must always make sure that the amount protein is sufficient when feeding processed food.
How Often Should I Feed my Arowana?
From juveniles, arowanas grow extremely fast; hence, they need a lot of energy and food. Small arowanas should be fed twice a day with quality food to keep up with their rapid growth rate.
As they grow bigger, their growth slows down along with their metabolism. Naturally, they’ll taper down their appetite and accept less food. You could feed sub-adults to adults once a day.
If you’re wondering if it’s possible to overfeed your arowana (like, nobody wants an exploding arowana on their hands!) it pays to know that arowanas will ignore food when they’re already full.
You should feed them as long as they are still accepting food. Just make sure to remove all uneaten food right away to avoid spikes in ammonia levels.
Pro Tip: Keeping the shell or exoskeleton on shrimp and prawns are known to improve the red pigmentation on Arowanas.
Temperament and Suitable Tank Mates for Arowanas
Aside form the silver and black arowanas, all arowanas are known to be territorial and aggressive.
The Australian is the most aggressive of the bunch and is known to attack and kill all tank mates when they reach 12” or more.
Arowanas are known to attack their own kind as well:
They usually don’t tolerate the presence of other arowanas around them- even if that arowana is of another species.
Because of this, I wouldn’t recommend keeping more than 1 arowana in the same tank, especially for beginners.
But just because they’re aggressive to doesn’t mean that they categorically can’t be kept with any other fish:
The general rule is that the other fish should be big enough not to be eaten, yet docile enough to not bully the arowana.
Popular choices are the peacock bass (Cichla sp.), hooks (Myleus sp.), stingrays (Potamotrygon sp.), big catfish, and other docile monster fish.
Also important to note:
Don’t be too eager to add one monster fish after another. There are a lot of species of monster fish, such as the infamous red tail catfish (P. hemioliopterus) and alligator gar (A. Spatula), that could easily outgrow and eat arowanas.
Pro Tip: Knowing the growth rate of monster fish would help you time the introduction of a fish in a community so that they won’t be too small or too large at any given time.
As your experience and knowledge with regard to arowanas continues to grow, you’ll find people successfully keeping arowanas in species only communities.
But as a beginner, this is not advised as it could be a very costly mistake.
At first, caring for such a large fish can seem daunting and overwhelming to any fish keeper- both novice and experienced alike.
However if you have the time, discipline, and the means to consistently provide for the needs of the arowana, it’s absolutely one of the most beautiful and majestic fish you’ll ever own.