Why Is My Arowana Fish Not Swimming Straight? {Signs of A Deeper Illness}

Have you noticed recently that your Arowana is having issues swimming? Are you wondering why is my arowana fish not swimming straight?

What are the signs your arowana has swim bladder disease? How do you treat arowana swim bladder disease?

In this article, we will figure what’s going on with Arowana not swimming straight.

Why Is My Arowana Fish Not Swimming Straight?

There could be a couple of reasons why your Arowana fish is not swimming straight. Your Arowana fish could potentially be stressed. The most common reason for Arowana fish swimming slanted is because they have swim bladder disease.

Arowanas suffering from Swim Bladder Disease display symptoms like as floating, head pointed down, tail up, upside down, or sinking.

Swim Bladder Disease is commonly induced by two factors:

1. Constipation resulting swim bladder impingement.
2. Swim bladder organ infection, or both infection and constipation.

Arowana Fish Not Swimming Straight

Why Is My Arowana Fish Swimming Slanted?

They swim slanted because their stomach is bloated and it changes the Arowana fish’s buoyancy, hence why they aren’t swimming how they typically would. Here’s a tip you can try before we dive deeper into possible diseases:

Lighting Trick

Turn off the light above the tank and re-observe. If it begins to swim straight after turning off the light, this indicates that the light’s location is forcing the Arowana to travel sideways. Then, move the light upwards so that the fish is not influecned by it.

Signs Your Arowana Has Swim Bladder Disease

There are a couple of different signs which suggest that your Arowana fish potentially might have swim bladder disease. If you notice any of these signs, you should take action immediately.

1. Abnormal Swimming

The most common sign of swim bladder disease is abnormal swimming. They exhibit this by swimming nose faced down, tail faced upwards, swimming upside down, floating, sinking, and generally not being able to maintain a normal position. It’s not common for fish to do this, so you must take action as soon as you notice.

2. Not Eating

Sometimes when a fish has swim bladder disease, they will continue to eat as expected, but some fish will stop eating altogether.

3. Distended Belly

If you notice that your fishes belly is swollen, this could be a sign that your fish might have swim bladder disease as it can increase the pressure inside their stomach.

4. Curved Back

Another symptom of swim bladder disease is a curved back. This, however, could mean something else, it’s best to have your Arowana fish checked over by a marine vet.

YouTube video

How Do I Know if My Arowana Is Stressed?

We can talk about lack of appetite or lethargy and sliggushness, but the first sign of stress to look for is:

Strange Swimming

When Arowana are disturbed, they frequently exhibit unusual swimming patterns. Your Arowana may be stressed if it is:

  • swimming wildly without going anywhere
  • smashing at the bottom of his tank
  • rubbing on gravel or pebbles
  • locking fins at the side

If you suspect your Arowana is stressed, you should treat him as soon as possible. Stress, if left untreated, can lead to serious and perhaps deadly illnesses.

How Do You Treat Arowana Swim Bladder Disease?

Thankfully, swim bladder disease can be treated, and we’re here to tell you some of the different ways that you can help.

  1. Reduce The Water Level
  2. Separate From Other Fish
  3. Reduce Feeding
  4. Change The Water Conditions
  5. Add Aquarium Salt

1. Reduce The Water Level

It is essential to make sure that your Arowana fish does not feel stressed whilst they are going through their treatment. To ensure this, make sure to reduce the water level, but leave enough water so that the Arowana fish can remain afloat.

2. Separate From Other Fish

If you keep your Arowana in a tank with other fish, it would be best if you separate your unwell Arowana into another tank where you can treat them separately, this might also help to destress them.

3. Reduce Feeding

Whilst your Arowana fish is being treated, we would recommend not feeding at all for the first three days. Then feeding should be minimized; this means cutting the amount of food that you would usually provide them.

Start small, and once your Arowana fish is getting better, you can start to increase the amount you feed it slowly.

4. Change The Water Conditions

You’ll need to change the water conditions whilst treating your Arowana fish, and this is why we suggest that it is best being separated from the other fish. The water temperature during treatment needs to be between 78 and 80 degrees Fahrenheit.

5. Add Aquarium Salt

Add aquarium salt to your Arowana’s tank. The chosen type of salt that you purchase will display the correct dosage for you to use.


Arowana should glide up and down the tank with ease, and its turns should be fluid and beautiful. When swimming, its body should be perfectly level horizontally. If it is not and is at a small angle, it might indicate a swim bladder problem.

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Hello, I'm Jason. I'm the guy behind HelpUsFish.com. I volunteer at my local fish shop and I created this site to offer tips and advice on the fish I care for.