The Arowana Aquarium

 

In this chapter, we will discuss the aquarium you will need to keep these marvelous fish. We will talk about our own experiences and ideas as well as things we found while talking to other people.  

Before we start, one point should be addressed. In this chapter we will discuss tanks which are suitable for keeping arowana. There is always a big discussion whether certain tank sizes are big enough to hold a fish and especially a big fish. From an ethical point of view it is always best to keep fish in the biggest tank possible but this does not mean that smaller tanks are unsuitable. Size is not the most important thing in proper fish keeping.

Some terms:

” = inch = 2.5cm

g = gallon = 3.8 liter

ft = feet = 30cm

 

Asian Arowana

 

Tank size:

Asian arowana can reach lengths of around 28” in most aquariums. This will however, take several years.Young arowana can be kept in small tanks of 40-50g. Keeping water levels low (50-60% of tank height) at this stadium will reduce stress for the fish. When the fish grow bigger, we recommend a tank of 6 x 2 x 2 ft or bigger. In Asia, arowana are usually kept in relatively small tanks. The fish do great in smaller tanks when water parameters are kept pristine.

Asian arowana can be jumpers so make sure they can not end up on the floor. We personally have never had an Asian jump but I know other people who have. Use some sort of lock or a heavy weight to keep the covers down.

 

Water parameters:

Asian arowana are very hardy fish and capable of handling most water parameters. Although they are capable of handling a lot, we do strive to keep water parameters as good as possible to make the arowana thrive.

Temperature should be kept between 78-86 ºF but situations where higher temperatures are required are usually not a problem for the arowana. In Asia, during warm seasons, arowana keepers struggle to keep temperatures below 86 ºF and the arowana's seem to have no problems with this.

PH and hardness are not very important although lower values tend to promote color and mimic natural habitats. Slightly soft and acidic water is used at the arowana farms in Asia and the original habitat of these fish has a pH of 5-6.  

We have successfully kept Asians at pH 7-7.5 and we recommend not going much higher. If needed, adaptive measures should be taken.

Low waste levels are important and we always strive to keep NH3, NH4 and NO2 levels at zero and NO3 levels below 100. Regular water changes and good filtration are a must to keep these animals. We recommend changing at least 25-30% of the tank water each week.

Conductivity in natural arowana habitats is quite low, maxing around 200μs and the arowana will appreciate low values.

Stable water parameters are important for the fish’s health and coloration: the more stable, the better the color.

Make sure the heater (if it’s used in the tank itself) has a heater guard, as arowana are big and powerful and easily capable of destroying the glass of the heater. This is obviously not good for anybody or anything and can be prevented by using these handy plastic guards,

 

Decoration:

We do not keep much decoration in our arowana tanks. The less ornaments, the less chance the arowana has to damage itself. Wood and rocks can offer the arowana the possibility to grate and damage itself. Some small pieces of wood on the substrate will not be much of a threat but larger, higher pieces will eventually make the arowana loose scales or damage itself.

We have seen many people with nice pieces of wood or rock in the aquarium which in the end had to be removed due to the arowana losing scales or hurting itself.

Smaller arowana, which are still insecure, might be given some floating plants or something else to provide shelter but as soon as the arowana becomes bigger it will not need such things.

Substrate is not important but if you choose for substrate it has to be non sharp as the arowana sometimes takes some in its mouth and might damage itself doing so.

Arowana do not seem to mind a bare bottom.

Lights for arowana tanks will be attended to in the chapter Color Enhancement. For arowana health, the amount of light or the light color is not really important. The amount of light hours isn’t really important for general health either but this will also be discussed in the chapter Color Enhancement.

 

A night light is not only cool for the owner to see his/her fish during the nightly hours but it will also calm the arowana. Asian arowana do not like total darkness and might become stressed or skittish and start jumping with all negative consequences you can think of. As night lights are quite cheap we recommend them. If your room is still quite light at night it’s obviously not necessary.

 

Tank mates:

There are many tank mates possible for Asian arowana. It does depend on the variety of arowana and the character of the fish itself. Red tail golden arowana are more aggressive than red arowana and tank mates must be selected with great care. Size does not always matter as arowana can bully other fish which do not fit its mouth.

As said, there are many possibilities and we do not want to discuss them all so we made a list with species that worked for us:

-          Stingrays

-          Big clown loaches

-          Bigger plecos

-          Knife fish

-          Gars

-          Polypterus

-          Datnioides

-          Other arowana

-          Parrot fish

-          Discus

-          Big catfish like niger cat, tigrinus etc

-          Big cichlid species like cichla and oscars etc

-          Chacarins like ATF, Dorado etc

 

 

 

 American  arowana

 

Tank size:

American arowana are the biggest species of arowana available in the pet trade business. With lengths of close to or even over 1 meter, a big tank is required to keep these animals for life. This being said, younger and smaller specimens of these fish can very well be kept in tanks of 4-5 ft. Adult animals, especially of the silver arowana, will need a tank of 10 x 3 x 2 ft or preferably bigger.

Very young arowana can be kept in small tanks of 40-50g. Keeping water levels low (50-60% of tank height) at this stadium will reduce stress for the fish.

As silver and black arowana are notorious jumpers, it is important to seal the tank with care. Probably most arowana deaths occur through jumping out of their tanks. Some sort of lock will look good and makes sure the fish do not end up on the floor beneath the aquarium.

Water parameters:

Water parameters for silver and black arowana are quite similar to the above mentioned values for Asian arowana. They are hardy fish but prefer slight soft and acidic water. Temperature should be between 77-86 ºF with an ideal value of 78-80 ºF.

Again, for waste levels things should be considered the same as written above.  

Decoration:

See above as this is also the same for American arowana as for Asian arowana.

Tank mates:

Silver arowana tend to be a bit more aggressive and sturdy than black arowana, who are actually quite timid and friendly towards most fish that do not fit in their mouth. This is important when choosing tank mates. Where silver arowana can easily be kept with more aggressive tank mates, black arowana might be overrun if placed with the wrong fish.

In the end it is also very much depending on the fish itself. Remember that the mouth of the arowana is very big and small tank mates might go missing suddenly if placed with these fish.

Again, there are many possibilities and we do not want to discuss them all so the same list of tank mates as shown above can be used here.