Fish Swimming In Circles – Explain The Phenomenon In Detail

Fish Swimming In Circles

Understanding some unusual behaviors of fish is very important in the process of raising ornamental fish. In this post, Aquatic 247 will answer the question: What is a fish swimming in circles? Why is my fish swimming in circles? How to solve a phenomenon?

What is a fish swimming in circle?

The phenomenon of fish swimming in circles is when the fish continuously swims in a circular or spiral orbit instead of traveling straight. Frequently, the fish is unable to control its swimming direction and may lose its equilibrium. This behavior can be a sign of a health issue or of the breeding season.

Fish Swimming In Circles
Fish Swimming In Circles

Why is my fish swimming in circles? 

There are many reasons why fish spin in circles. Below are some reasons that you can refer to.

Hungry fish 

Like other animals, fish need food to sustain life. If it is not provided with enough food, it will be able to do many actions, such as fish spinning in circles and swimming fast, etc. So, let’s feed your fish.

Sick fish

Ammonia Poisoning 

The ammonia and nitrite levels in the tank should never exceed zero. Nitrate levels should be 30 ppm or lower. Ammonia levels may increase suddenly if the following changes occur:

  • Overfeeding the fish
  • Decaying organic materials in the tank
  • Poor water quality
  • An overloaded fish tank
  • Aquarium filter blockage or decreased flow rate
  • The use of drugs results in the death of bacterial colonies


  • Swimming in circle
  • Rapid breathing
  • Body colour darkened
  • Appetite loss


  • Immediately cease feeding the fish.
  • Make minor, regular water changes.
  • To aerate the fish tank, use either an air or water pump
Fish Swimming In Circles
Fish Swimming In Circles

Whirling disease

Myxobolus cerebralis is a parasite that causes illness in fish. The parasite penetrates the fish’s body and infects its brain and ears, resulting in nerve damage. Furthermore, immature fish are thought to be particularly vulnerable to its effects.


  • Spin in a spiral
  • Spine is torn
  • A dark-colored tail

There is no therapy or cure for Whirling Disease in fish. So, keeping your fish from becoming infected is the best option.

Bladder disease

Bladder disease is a popular disease that causes functional disorders of swim bubbles. There are many factors that contribute to this condition:

  • Overfeeding fish
  • Swallow too much air
  • Infection


  • Fish float on the water surface or lie on the bottom of the aquarium
  • Abdominal bloating
  • Spine is curvy


  • Stop feeding the fish immediately (at least 24 hours).
  • Put your fish in a salt solution to reduce tension.
  • Maintain your aquarium’s temperature between 75 and 80 degrees Fahrenheit.

The fish tank condition is bad

The bad fish tank condition is the main cause of the fish stress. In harsh conditions, it leads to a depletion of oxygen.

It is important to check the water parameters in the aquarium from time to time. Acute stress in fish can be caused by a variety of factors:

  • Low oxygen levels
  • High ammonia
  • Nitrate levels
  • Temperature variations

Territorial behavior

Fish swimming in a circle can be territorial behavior, especially if your aquarium is in optimal condition and the fish seem healthy.

It is just the act of swimming about a certain area to establish boundaries and inform other fish that they are not welcome in their domain.

Exposure to chemicals

The medicine is used to treat sick fish, but it changes the chemical composition of the water, affecting the original parameters.

To cure ill fish, utilize a quarantine tank rather than administering medication to the main fish tank.

Fish Swimming In Circles
Fish Swimming In Circles


Why is my fish shimmying?

Shimmying is a symptom, not a disease, and occurs when a fish loses control of its nerves and muscles. Fish with shimmies may be suffering from stress, water chemistry problems, or even poisoning.

The fish may occasionally vibrate, shake, or twitch its body for brief periods, as well as have hazy eyes, bloating, and excessive slime production.

Why is my fish twitching? 

Twitching is a spontaneous muscular contraction that occurs when a fish moves rapidly and jerkily.

This is an involuntary movement that affects the fish’s body.

  • Infection: If the fish has red skin, swelling, difficulty breathing and discoloration.
  • Stress: Not being able to adapt to the new environment.
  • Poor water quality: Water temperature and water quality are not correct.
  • Parasites: Fish are working hard to ward off pesky parasites.

Why is my fish spinning uncontrollably?

My fish is spinning uncontrollably from high stress. However, if the fish develops a rash with white spots on the body, gills, and fins, it could be due to White Spot Disease or Ich.

Why is my fish swimming erratically after a water change? 

Fish can swim erratically after a water shift, which is usually caused by a condition known as osmotic shock.

Osmotic shock occurs when a fish is unable to manage its intake of ionic substances, causing it to release or absorb an excessive amount of fluid.

In conclusion 

Fish swimming in circles is a common phenomenon. If the fish is not sick, this is a behavior of them. If the fish is sick, we have some measures to deal with this phenomenon.