Whether in the wild or in captivity, fish normally have swimming patterns and most kinds rarely change it.
Tiger Barbs, for example, are known to swim around the middle portion of tanks and aquariums.
Some kinds of fish have the ability to change their swimming pattern depending on the stage of life or even due to drastic changes in the environment.
That is not common with Tiger Barbs.
These fish, however, tend to display a momentary different swimming pattern and move vertically for a while as shown in the video below:
Why Do Tiger Barbs Swim Vertically
As for the reason why Tiger Barbs randomly swim vertically, there are THREE main theories and, if your fish are displaying such behavior, we strongly suggest you check for the reason behind it.
- Swim Bladder Disease
I say so because one of the reasons why your Tiger Barbs would be swimming vertically is related to an illness called Swim Bladder Disease.
If you are an experienced fish keeper, the Swim Bladder Disease (SBD) should not be something new for you.
Swim Bladder Disease is an illness that affects the organ that names it and causes the fish to lose control over it.
The Swim Bladder is the organ that helps the fish control the amount of air inside their bodies.
Whenever they lose control over it, it may happen that the amount of air inside the organ gets too big and, due to that, the fish is constantly pulled up when they attempt to swim.
This vertical swimming, thus, is the response of the animal to the force that is pulling it toward the surface of the water.
Swim Bladder Disease can be caused by a series of factors, such as constipation, infection, bad eating habits, or a generally poor diet.
Owners of goldfish normally see their fish more commonly suffering from the disease due to constipation.
I have a goldfish tank too and I am quite familiar with this disease as it attacks my goldfish too.
Tiger Barbs are not so often affected by the disease but that doesn’t mean they are free from it.
- Consume Too Much Food
As it goes, your Tiger Barbs may end up consuming too much food and end up taking longer to digest.
During that time, the excess food may end up pressing against the bladder, causing a momentary loss of control.
I am using an automatic fish feeder with timer as below, but the disadvantage is sometimes it is quite difficult control the amount of food it will release.
And it might overfeed the fishes in my tank.
It can also happen that your Tiger Barbs when reaching for the surface for food swallow air while eating as shown in the image below:
Other reasons for Swim Bladder disease include the fish being fed the wrong food, which can ferment in the fish gut, parasitic or bacterial infections, and even sudden changes in the temperature of the water.
Read: What Do Tiger Barbs Eat
Anyhow, make sure to check if your Tiger Barbs are suffering from this disease when they display the change in their swimming patterns.
- Tiger Barbs are just relaxing
Luckily, this could be the most pleased reason why vertical swimming can happen.
This often happen during the time Tiger Barbs are digesting food or almost falling asleep.
Whenever these fishes want to change to a chilling or relaxing position, they tend to move upside down and even closer to the bottom of the tank.
So, if your Tiger Barbs are swimming vertically it doesn’t necessarily mean they are suffering from the Swim Bladder Disease and may be simply taking a moment to relax.
Since every tiger barb does not have the same patterns, please monitor the condition of your tiger barbs closely if they keep repeating the same vertical swimming behaviour.
