Arowana Water Temperature

Arowana Water Temperature, Tank Conditions & More


Are you thinking of purchasing an arowana for your aquarium? If so, one of the most important things to consider is the water temperature, because your fish will die if you don’t provide it with the right conditions.

Arawanas prefer to be kept in tanks that are between 73 and 82 degrees F, which is a fairly narrow range. If the water gets noticeably hotter or colder, they are likely to die, or at least become stressed, which will leave them vulnerable to diseases. You need to be careful and monitor your tank’s temperature in order to keep your fish healthy.

In this article, we’ll explore what sort of water temperature arowanas need, and what other tank conditions you need to provide. This will ensure that you have the best possible setup for your inhabitants.

Arowana Tank Conditions

Getting the tank right for an arowana is important. These fish swim close to the surface, which means that the size and length make a big difference, and the height is less relevant. Arowanas get very large, so you need a minimum of 250 gallons, preferably wide and long, to keep them in once they reach adulthood.

If you purchase a juvenile, you can keep it in a smaller tank of around 60 gallons, but you should be aware that these fish grow rapidly and will soon require a bigger space. They can gain around 2 inches per month in some conditions, so having enough space for them is critical.

You also need to think about the pH balance of the tank. Arowanas like to be kept between 5.0 and 7.5, and preferably somewhere in the middle of the two (6ish is ideal). Water hardness also matters, and you should aim for 1 to 8 dKH.

To keep an eye on all of these parameters, you should be aiming to test your tank water every 3 days or so. Arowanas are not particularly easy fish to keep, and if one of the levels slips out of balance, they may get sick and die. These fish are best for experienced hobbyists.

Arowanas also like to have some plants in their tanks, although they are less interested in foliage than some kinds of fish. Providing just a few should be sufficient, as long as the fish have enough space to swim around. Use fine gravel for the substrate so you can root the plants firmly.

You should add a strong filter to the tank, and make sure you are doing 25 percent water changes once per week to balance the nitrates and ammonia.

Finally, you should make sure that your fish tank has a weighted lid. Arowanas often jump out of the water to hunt prey in the wild, and there is a high risk of your fish killing itself if it ends up outside the tank by mistake.

Do Arowana Like Warm Water?

Arowanas prefer warm water, yes. They are native to warm South American streams and tributaries. They require a minimum of 73 degrees F, and most people recommend keeping them above 75 degrees F.

That will generally mean you need a heated tank, because most people’s homes are cooler than 75 degrees F. Even if you keep your home fairly warm, you need to ensure that the fish tank doesn’t dip down on cool days, so a heater is a preferable and more reliable option.

It should keep the water stable and ensure that the fish are happy.

Can Arowana Fish Live In Cold Water?

In theory, an arowana can cope with cool water for a while, and some people do attempt to keep them in unheated tanks. However, there is a high risk that your fish will get stressed, which will often lead to it getting sick and dying.

Because they are so large, a lot of people want to keep arowanas in outdoor ponds, which tend to be more spacious than indoor fish tanks. However, these are not generally heated, so unless you live in a warm part of the world, there is a high risk that your fish will get too cold.

A cold arowana is likely to be stressed and vulnerable to diseases and parasites, and there is a risk that it will die if the temperatures drop lower. Arowanas may tolerate cool water, but they can’t cope with true cold.

Can Arowanas Live Without An Air Pump?

Arowanas can survive without air pumps if they are in a suitable tank. A bigger tank should have enough oxygen in it for your arowana to survive, but if you see your fish gasping at the surface, this is a clear sign that more oxygen is needed.

Having enough agitation at the surface of the water is often enough to keep an arowana happy, even if you don’t have an air pump. However, if your fish is in a more crowded tank or if the surface is very still, it may be necessary to add an air pump so that you can oxygenate the water.

Do Arowana Like Water Currents?

There is mixed information about whether arowanas like having currents in their tanks or not. These fish come from rivers where they are likely to experience a reasonable amount of water movement, but they may not enjoy having strong currents in their tanks, especially if the flow of water is directed into the center of the tank.

Instead, provide some flow that they can choose to swim in if they want to, but that they can escape from if they prefer. This will offer the best of both worlds and help to keep the water rich in oxygen at the same time.


Providing arowanas with everything they need is important, but these large fish are not considered very easy to keep. Making sure that their tanks are warm enough and spacious enough is one of the first big challenges, but you should also think about oxygenation and water movement in order to keep your fish happy and healthy.