Guppies swim at the top of the tank when they feel suffocated due to the lack of oxygen in the tank water. Guppies swimming at the top is a clear indication that they are struggling for air. Use an air pump to increase the oxygen levels of the tank water.
There could be other reasons as well for your guppies to swim at the top of the tank. But first, let’s understand how guppies breathe.
How Do Guppies Breathe?
Like human beings, guppies also need oxygen to breathe.
Guppies breathe by pumping out water through their gills, which derives oxygen from the water.
If you have live plants in your fish tank, they help maintain the required oxygen levels in the tank water.
Plants inhale carbon dioxide and exhale oxygen into the water.
Guppies, on the other hand, inhale oxygen and release carbon dioxide.
So this cycle benefits both; your guppies as well as the plants in your aquarium.
However, if your guppies don’t get sufficient oxygen from the water, they will suffocate.
This, in turn, will lead to restlessness in your guppies, and they would swim at the top of the tank.
What Causes Guppies To Swim At The Top Of The Tank?
If you notice that your guppies are staying at the top of the tank, then it is undoubtedly a matter of concern.
Your guppies are just not comfortable in the tank.
There are two main reasons that cause guppies to swim at the top of the tank:
- A shortage of oxygen or lack of oxygen in the tank water.
- Your fish tank is too deep, and your guppies want to rest their gills. Swimming at the top allows your guppies to absorb more oxygen by floating.
If you have female guppies or guppy fry in your tank, then their behavior is also the same.
They will also swim at the top of the tank due to the lack of oxygen supply in your tank water.
So you need to act fast if you notice guppies staying at the top of the tank as they might be in distress.
It is not normal for guppies to swim at the top of the tank.
But why?
To understand this, you need to understand the swimming behavior of guppies.
Swimming Behavior Of Guppies
Guppies are a very peaceful species. They are friendly creatures that get along easily with other fish.
So to understand guppies swimming behavior, you need to understand their pattern of swimming.
Guppies usually swim actively all around in the tank.
Their swimming is not restricted to a particular place or a specific manner.
Your guppies will scatter everywhere in the tank. They will swim independently in any direction in the tank.
Their random swimming pattern is attractive and makes them look playful.
If you notice any change in their swimming pattern, then there is certainly some problem with your guppies.
They need your immediate attention.
You should immediately check the water and lighting.
However, those are not the only things to check.
Sometimes guppies can swim at the top of the tank if they are hungry and waiting for some food to be served.
Why Are Guppies At The Top Of The Tank After A Water Change?
Changing the water of the fish tank is a good practice. You should change the tank water as and when required.
But after changing the tank water, you might notice your guppies hovering at the top of the tank.
It is natural for guppies to be at the top of the tank after a water change.
Guppies swim at the top of the tank after a water change because it takes them some time to acclimatize to the changes in the water.
The surface of the water contains the highest level of dissolved oxygen.
If your guppies aren’t getting enough oxygen inside the tank, then they will come to the top for oxygen.
However, keep in mind that the reason for insufficient air can be something else as well.
For example, if the water in the tank is warm, it will hold less oxygen.
This will eventually lead your guppies to swim to the top of the tank.