Arowana community tanks


Arowana blogger
Here are some recommendations for hobbyists who want to keep more than one Asian arowana in a community setup:

For aro com tanks, the more Asian arowana you can put in together, the better, with 5 being the lowest number I would recommend. 2 will almost never work (though I do know of cases where it has), 3 will end up with one being bullied and becoming a runt over time (or worse). 4 can end up in the "four corners of death" scenario where each fish stakes out a corner with the dominant fish also controlling the open middle area. 5 or more generally works. I have heard of Feng Shui belief that "9 dragons" is an auspicious number.

* Asian arowana and South American arowana can work, though you should try to have the South American arowana be a little larger if possible since the Asian arowana tend to be more aggressive.

* If you have a lower number of arowana and are worried about aggression, consider installing submersible power heads to create a clockwise or counter-clockwise current such that the fish spend more time swimming against the current than fighting with each other.

* If you experience aggression between the fish and a dominant is causing trouble consider the following: 1) remove the dominant fish for a week to another tank; then rearrange the com tank decorations such that it looks like a "new" tank. Return the dominant fish and see if it now behaves less territorial/aggressive.

* Get some fast moving "dither fish" to help disperse aggression. Various species of silver dollars, tinfoil barbs, prochilodous (flag tail), peacock bass, etc., work well. Avoid slower moving aggressive tank mates like oscars. Angelfish and discus can work okay provided they are not close to being "bite size" in relation to the arowana.

In terms of aggression, there is a long held belief that RTG (red tail gold) may be the most aggressive, with super reds being the most passive. Super reds tend to be the largest when full grown, getting at large as 30 inches.

Large pieces of driftwood that protrude into the swimming area of the arowana are not a good idea.

As always, keeping the tank water nice and warm (around 28-30 C, same as for discus) is good; keep in mind Asian arowana come from still or slow moving tropical waters right around the equator.

A tablespoon of aquarium salt per 10 gallons of water is always a good idea, as are weekly 20% water changes and monthly cleaning of your canister filters. 24/7 drip systems are ideal for water control.

A Ph of 6.5 to 7 is ideal (same as for discus).

It is helpful if you can lower the water level about 3-4 inches from the glass lids as the fish do jump and you will hopefully reduce injury if you have a bit of surface clearance.

OPEN TANK LIDS lead to jumping arowana, which is the #1 cause of death. BEWARE!


Arowana blogger
Thanks Mike :)

I should throw in a video of a functioning Asian arowana community tank; here is a good one from the back room at Concept Aquarium in Calgary: