The Silver Arowana, also known as the Dragon Fish or Monkey Fish, is a freshwater fish indigenous to South America.
Renowned for its hunting ability and large size, this fish is one of the most iconic around and will be the prized possession of any hobby aquarist.
Whilst not generally recommended for beginners, this fish can make a fantastic addition to an experienced keeper’s tank.
Before we explore our complete guide to Silver Arowanas below, I’ve condensed the key information down into a facts table shown below.
|Size:||Up to 3 Foot|
|Minimum Tank Size:||250 Gallons|
|Tank Set-Up:||Freshwater: Rocks, and Plants|
Overview of Silver Arowana
Also known as the Dragon Fish, Monkey Fish, and occasionally misspelt as Arawana and Arahuana, this fish is adored by many hobby aquarists.
Arowana are strong powerful swimmers, and can be fairly aggressive at times. They are a predator fish that can grow up to 4 foot in size and weigh in excess of 6kg. When raised in captivity you should expect an Arowana to have a lifespan of 10-15 years.
If you ever encounter them in the wild, you will notice their unique hunting style. They have a huge leap which allows them to hunt animals on low level branches etc.
They also have the ability to survive short periods of time out of water, by using their swim bladder.
In general if you are looking for an Arowana, Silver Arowanas are the least restricted to import regulations and because of this are also the cheapest variant of Arowanas available.
Their huge size, precarious nature and long lifespan make them a fish that only experienced aquarists should consider.
Silver Arowanas’ Appearance
The Silver Arowana is a much sought after fish, normally the crowning jewel in any collection.
They are large and silver colored, and can grow up to 4 foot in the wild, however when kept in captivity you should expect them to grow to around 3 foot. In terms of weight the average Arowana will weigh around 4.6kg (10lb) when fully matured.
Its most distinguishing characteristic is its jawline. Affectionately referred to as a ‘drawbridge’, their mouth is nearly vertical.
As for their body, you will see they have large pearl-like silver scales across their entire body. As juveniles these scales can have a blueish tint to them.
Their long sleek body appears flat when viewed from the side, and if you look closely you will notice their dorsal is almost fused with the caudal fin.
Females are generally ‘thicker’, with males being more slender and having a larger anal fin.
As for their growth rate, they start out small (around 4 inches after their egg sack has been consumed), but grow exceptionally fast. During their first year they will grow 2 inches each month, so you need to make sure they are well fed and have plenty of space in their aquarium.
For a large fish they can be surprisingly skittish. Arowanas will get scared from sudden movements, for example when you approach the aquarium quickly, or turn the lights on.
You should make sure to keep your Arowanas in a tank placed in a low foot-traffic area. This prevents them getting startled each time you walk past the aquarium.
When watching your Dragon Fish, you will notice they spend most of their time swimming close to the surface of the water.
However it should be noted that Silver Arowanas are notorious jumpers. It’s been claimed that they can jump up to 3 meters high. They are most likely to jump when they are new to an aquarium or are placed in an aquarium which is too small for them.
When placed in an aquarium that is too small for them, they will repeatedly try to jump to freedom. Even if the aquarium is covered, they will still jump and can injure themselves when bouncing off the lid.
This is why it’s crucial you only place Arowanas in a suitably sized tank.
Habitat and Tank Requirements
As mentioned in the appearance section above, Silver Arowanas are large fish and strong swimmers. They quickly outgrow most hobby aquarist tanks, and require a tank at least 250 gallons in capacity.
Juveniles can be raised in a smaller tank of 60 gallons, but will quickly need moving out into a larger aquarium.
If they aren’t moved into a large enough tank, you will quickly start to have problems with your Arowana, most notably body deformation and reduced lifespan.
The substrate should consist of fine, small gravel. The tank should be sparingly planted, and have lots of open space for them to move around in. If you like to decorate your aquarium, you can do so with driftwood, rockwork and sturdy plants. You should avoid plants with weak roots as they can be dislodged by Silver Arowanas.
Finally, it should be noted that Silver Arowanas are notorious jumpers, so you need a very heavy cover to stop them jumping out of the tank.
You should aim to keep the water temperature anywhere from 75-82°F. Meanwhile, pH levels should be 6.5-7.5, and water should be soft to moderately hard.
As Silver Arowanas are particularly susceptible to poor water quality, strong water filtration is required, in addition to weekly water changes of 25%.
Like other freshwater fish, Silver Arowanas are tolerant to changes in these conditions; however you should aim to keep your water within the tolerances outlined above.
Arowanas are easily spooked, so you should keep the aquarium in a low traffic area.
Silver Arowanas Compatibility and Tank Mates
The first thing to remember about Silver Arowanas is that they are first and foremost a predator fish. This has implications for their compatibility and which fish can share a tank with them.
Let’s start by looking at them as juveniles.
When they are young they are particularly susceptible to bullying by more aggressive breeds. So you should bear this in mind when placing them in an aquarium.
You should also know that when young, they can be kept together and raised. It’s recommended that you keep 6 or more Silver Arowanas together. This prevents the smaller ones from being excessively bullied by the larger Arowanas.
Now let’s look at the compatibility and ideal tank mates for adult Silver Arowanas.
It probably isn’t surprising to hear that finding ideal tank mates can be difficult. This is because they are targeted by aggressive fish due to their size. On the other end of the scale, smaller fish aren’t good tank mates as they usually end up being eaten by Silver Arowanas; remember they are a predator fish.
However, there are still lots of species which can live with Arowanas.
When assessing fish to keep with your Arowana, keep in mind these three general rules:
- You want to find peaceful yet slightly aggressive fish.
- Fish should also be large enough that they can’t be eaten by the Arowana.
- You should introduce the Arowana to the tank first.
So good examples of this would be: Green Terrors, Oscars, Knifefish, Large Plecostomus, Parrot Cichlid, Angelfish and Catfish.
Remember though that temperaments of individual fish can vary hugely, so always have a backup plan if they don’t ‘get along’.
Keeping Arowanas Together
If you plan on keeping multiple adult Arowanas together, do so cautiously. They generally don’t get along well together. If you are insistent, you should keep at least 6 of them together and keep them in a large natural pond (or an aquarium of similar size).
Diet and Feeding Requirements
Silver Arowanas are generally considered to be carnivores, however they are occasional omnivores.
In the wild they will consume a wide variety of prey including: small fish, snails, large insects, rabbits, frogs and even snakes!
However, if given an option, their food of choice is normally small fish and crustaceans.
Arowanas have a distinctive hunting style. Due to the position of their mouth they can swim just below the water line before jumping up out of the water to catch their prey. They can also catch small fish by swimming beneath them and scooping them up.
When keeping these fish you want to make sure their diet is as close to what they would eat in the wild.
Their preference is a meat-based diet, which can include: earthworms, crab, crickets, shrimp, beef heart, krill and crustaceans.
You can also give them feeder fish. This allows you to watch them hunt which can be very absorbing. If you want to use feeder fish, I would generally recommend you breed your own, this way you can ensure the breeder fish are healthy.
If you are buying feeder fish from pet stores or online you can’t ensure they are healthy and you risk bringing disease into your aquarium.
If you’re worried about the expense of fresh meat, you can feed your Arowanas frozen food to try and keep the costs down. I have heard that some have been trained to eat pellets but this isn’t common.
Finally, it should be noted that juvenile Arowanas are very fussy eaters.
You should only feed them fresh/live food at this stage in their life. As they begin to mature (above 8-9 inches) you can introduce them to frozen foods such as krill.
In the wild Arowanas will normally lay their eggs at the start of the flood season (December – January).
Before spawning, they will pair off and build a nest. The female will then lay her eggs into the nest before the male takes the eggs in his mouth; Silver Arowanas are mouthbrooders.
These eggs are reasonably large in size and are orange/red.
The male will carry the eggs for around 50 days where they mature from an egg to larvae, to fry. At around 5 weeks after hatching they will leave their father’s mouth and start to find food.
Unfortunately there is only a handful of breeding success stories in home aquariums. These successes are also reported from tanks/ponds bigger than 500 gallons. For this reason, it’s generally not recommended to attempt to breed them from home aquariums.
The majority of Arowana available to buy today are sourced from Asian fish farms.
Is the Silver Arowana Right For Your Aquarium? (Summary)
The Silver Arowana is not a fish that is suitable for beginners.
Due to its large size and long life expectancy, only more experienced aquarists should undertake this challenge. It requires an enormous tank (at least 250 gallons in capacity) and finding suitable tank mates for them can be challenging.
They are considered to be carnivores and eat large quantities of food so this should also be considered before purchasing them. Though you could make your own fish food to save money.
In terms of price, the Silver Arowana is normally the cheapest type of Arowana available and should cost you around $40 for a small one.
If you are looking to get an Arowana, try to buy them when they are at least 8 inches long. By this time they have started to mature and are much hardier which means you will have a better chance of successfully keeping them.
Do you already keep Silver Arowanas? Let me know your experience with them in the comments below…