What are the common fish disease and behaviour

What are the common fish disease and behaviour

Just like humans, fish often have to cope with stress and their own complications. If you owned a fish at home, you will gaze into your aquarium and think about what a peaceful life it must be. A fish get to swim around all day in a spacious tank and get fed and cared for by their owner. It might sound ridiculous, but fish can get stressed in much the same way as a human do. Just like humans, though a stressed fish can lead to serious health complications, therefore it's important for owners to be able to recognize when your fish is stressed and what you can do to help.

Here are the symptoms that a stressed fish has


If a fish is stressed, they will not eat. It is best if you observe whether the tank has any leftover food, or by observing whether your pet fish will consume the food immediately when you feed them


The most obvious symptoms that you can observe are by the white spots on the body of a fish, other diseases can appear as a result of stress. If you observe this or any other visible ailments on your fish, you should talk to your veterinarian about the possible treatments.

Gasping at the surface

If a fish is gasping its mouth at the surface, this is a sign of stress brought by bad water conditions, usually a lack of oxygen

strange swimming

Strange swimming 

A stressed fish swims differently from a stress-free fish, a stressed fish will swim in an odd pattern. If your fish is crashing the bottom of the tank, hitting the sides of the tank, rubbing himself on a rock, or locking his fins at his side, most probably he is experiencing significant stress.

What are the factors that lead to a stressed fish?

Troubles with other fishes

Before introducing a new fish to your tank, you will need to know that not all fish get along with each other, they will feel cramped if they live with too many other fish or you are putting the wrong fish to the tank. Not only that, but it also leads to various problems in fish combativeness and water quality. If you have many fishes in the tank, try to distribute the food evenly, so that they will not run a kong fu fight in their tank. 

Other factors 

In addition, there are some other factors that lead to stress. One of these is the added chemicals or medications in the fish tank. When treating a sick fish, ensure he is properly quarantined. Improper diet can cause stress too, therefore you will need to know your fish's diet and do your best to adhere to it. Finally, banging the tank or causing loud noises can lead to fish stress as well. If you have children, as a parent you will need them to respect the fish's home. 

Low oxygen in a fish tank

How to determine insufficient oxygen in aquarium water 

Unfortunately, there is no flashing light or an alarm that goes off when the oxygen level drops too low in a tank. Aside from testing the water for dissolved oxygen, the only indication of trouble will be the behavior of your fish.

Your fish will react by moving around less. They will swim less vigorously and eat less often. As oxygen levels drop further, the fish will begin to show rapid gill movement as they are desperately attempting to get enough oxygen from the water by passing water over their gills.

Owner usually confused surface breathing with fish feeding at the surface, or fish that normally takes in air at the surface, such as labyrinth fish. Therefore you will need to know does your fish usually take in some air at the surface. It is normal behavior for them, but they will not remain on the surface taking a breath after breath

When any fish do go to the surface of the water for oxygen, they will gasp repeatedly, often with a wide-open mouth.

Causes of Low Oxygen

The number one reason for low oxygen in a tank is overcrowding. In fact, other oxygen-depleting factors rarely cause fatalities by themselves if the tank is not overstocked. If the tank remains overstocked, correcting the other factors will not fully solve the issue. Other factors that cause low oxygen include:

  • Overcrowding 
  • Elevated water temperature 
  • Lack of water movement 
  • Low lighting with live plants
  • Use of certain chemicals

Is my fish sick?

Dogs are unlike fish, when dogs are sick the symptoms are more significant and with your instinct, you will know that your dog is unwell, but it is hard for fish owners to know whether their beloved fish is sick. Here are the top 3 common diseases that your fish might have 




How to maintain a healthy aquarium water

Aquarium's environment 

An aquarium is a balanced ecosystem that relies on "good" bacteria to consume and convert the toxic chemicals produced by the fishes into less toxic chemicals that are safe and can be removed through regular aquarium maintenance.

When you first set up the aquarium, you will need to encourage the growth of these good bacteria. This process is known as "the cycling" it can take up to 3-7 weeks for these good bacteria to grow. We are able to reduce the cycling duration to 1-3 weeks just by following the simple steps below.

1) Set up and fill the aquarium with water. Remember to fill the aquarium without any fishes. Leave the aquarium to filter at least 24 hours to ensure all equipment is functioning properly and check whether the ideal temperature has reached. 

2) Introduce a few small fish such as danios or livebearers. The number of fish will depend on the size of the aquarium, you may ask a fish expert for advice. 

3)Sooner or later, the good bacteria will begin to form and balance the chemistry in the aquarium. Once the water is ready, you may introduce your new buddy to his new home. 

How do I care for aquarium water?

You will need to check your aquarium's water temperature daily, you should be getting a result of 74-82 degrees Fahrenheit, if any temperature that is above or below the temperature given, you will need to use an aquarium heater to keep a consistent temperature. Every week, you will need to replace 30% of the tank with clean water, and test the water's pH, ammonia, nitrate, nitrite, hardness, alkalinity, and chlorine. For monthly maintenance, you will need to inspect the filter; rinse the cartridge, carbon, and pre-filter if necessary, clean away any algae, clean plastic plants, and any kind of decorative items, prune some live plants if necessary.

Common fish behavior

fish behavior

It is important to know and understand your fish behavior. The way your fish acts and behaves indicates its health and environment your fish is living in. Some most common fish behaviors are explained as follows:


When fish are introduced to a new aquarium, most fishes show hiding as their natural and most common behavior


Many fish shows aggression as their natural behavior and always defend their territorial space until death. Some fish are not compatible to fit and house in the same aquarium, therefore you always be seeing them fighting against each other. 


The most common factor is improper water temperature. If water is too hot or cold, your fish will be inactive. Other causes may be overfeeding or improper water quality.

Gasping for air

Fish may be gasping air from the top of the tank and it can be due to improper water quality or due to insufficient dissolved oxygen in the water. Testing your tank water every day and investing an aerator will help you to solve the problem 

Sitting on the bottom

Fish behaves normally when they are spending lots of time at the bottom often and also sleep at their bottom of their tank. If your fish doesn't fit into this activity, it may be a signal that your fish is having a disease. A disease that is a cause of this behavior is a swim bladder infection, which is the result of a poor diet and poor water quality. 

Swimming Erratically

Fish generally swims erratically while playing or exercising but a consistent act of play or exercise will mean a stage where your fish can be unhealthy because of poor water quality. 

If you determine that your fish is suffering from stress, you should act quickly to treat him. If you left your fish alone for a long time, stress will lead to a more serious and possibly fatal disease. First, you should observe your fish behavior and test the tank's temperature to eliminate the cause. If this action doesn't improve your fish's condition, you should immediately contact your veterinarian about the possible solution. 

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