9 Reasons Why Cardinal Tetra Are Dying By Ich

As we all know, the cardinal tetra is one of the most popular fish in the aquarium hobby. It’s a beautiful and distinguished fish with iconic black and red coloring. However, many people are unaware that Cardinal tetra is dying by Ich – why?

Ich is a common health issue in tropical Cardinal tetra. But the reason why Cardinal tetra is dying of Ich is not always apparent why. Some of the suspected reasons why this is happening include:

  • Poor water quality
  • Lack of oxygen
  • Stress from transport and changes in the environment
  • Poor diet
  • Parasites

No matter the cause, it’s essential to take steps to protect your Cardinal tetra from Ich. This blog post will discuss nine reasons why these fish are dying from this disease and some tips on preventing it.

What Is Ich?

Ich, or white spot disease, is a parasitic infection that affects fish. The parasite attaches itself to the fish’s skin and fins, causing lesions that can quickly lead to death if left untreated. Ich is one of the most common diseases in aquariums and can result from various factors, including poor water quality, stress, and overcrowding.

How To Identify Ich In Cardinal Tetra?

The most apparent sign of Ich is the presence of white spots on the fish’s body. These spots can be small or large and may spread quickly if left untreated. Other symptoms of Ich include:

  • Small white spots on the fish’s body
  • Spots that spread quickly if not treated properly
  • Fish will become sluggish and may rub up against objects to scratch themselves (this is “flashing”)
  • Gasping at the surface of the water due to a lack of oxygen
  • Red patches on the skin due to inflammation
  • Loss of appetite and weight loss
  • eventual death.

If you notice any of these symptoms in your cardinal tetra, it is vital to take action right away.

Why Are Cardinal Tetra Dying Of Ich?

Ich has a life cycle of about 48-72 hours. It is a white spot disease and transfers from one fish through live food. Along with this, other aquarium inhabitants such as snails or plants exposed to it might also assist in the contraction of Ich. But the most common reason why Cardinal tetra is dying of Ich are:


Cardinal tetra is very sensitive to changes in their environment and can succumb to Ich quickly if they become stressed. Usually, it can occur for various reasons, such as overcrowding, bullying by other fish, or new aquarium inhabitants.

Lack Of Oxygen

Cardinal tetra cannot extract enough oxygen from the water if there is a lack of dissolved oxygen in their tank. Hence, if your aquarium lacks aeration or filtration, you will need to add an air stone and filter to keep the levels up.

Improper Water Parameters

Water parameters such as pH level, temperature, and water hardness can all affect the health of your fish. Therefore, it is essential to monitor these levels regularly to act fast if they begin to show signs of stress, making it more difficult for them to fight Ich effectively.


Ich is a parasite that can affect both fish and plants. Therefore, if you have an infestation of Ich in your tank, it is crucial to treat all of your aquarium inhabitants with a medication approved for use against Ich.

Poor Nutrition

A poor diet can also lead to a weakened immune system and make your fish more susceptible to Ich. So, make sure you feed them a quality diet consisting of meaty and vegetative foods.

Poor Water Quality

Ich thrives in poor water quality conditions. So, if you’re not keeping up with your tank maintenance, you provide an ideal environment for Ich to thrive and spread.

Low pH

Cardinal tetra does best in a pH of around neutral (pH of about seven). If your tank’s pH is below this level, it can cause stress and even death to your fish.


Cardinal tetra is a schooling species. So, it would be best if you kept them in groups of at least six or more. If you overcrowd the tank with too few cardinal tetras, they will not have enough space for themselves. As a result, they feel stressed out, making them more prone to diseases.

Lack Of Tank Mates

Cardinal tetra prefers the company of other fish species like danios, harlequin rasbora (Trigonostigma heteromorpha), or any small catfish that keeps it safe from larger predatory fish. If you keep them with non-schooling fish, it will make them feel less secure and more stressed.

How To Save Dying Cardinal Tetra?

The cardinal tetra is a beautiful fish popular in the aquarium hobby. Unfortunately, this species is dying from ichthyophthirius multifiliis, more commonly known as Ich. Although you can cure Ich in cardinal tetra, it can be complex.

If you want to save your Cardinal tetra from dying of Ich, you should prevent it from happening and provide the correct treatment.

Treatment Of Ich In Cardinal Tetra:

Some of the treatment methods for Ich in cardinal tetra include:

  • Quarantine of infected fish
  • Use of salt baths (sodium chloride) at a concentration of 0.05% for up to two weeks
  • Medication with copper sulfate or formalin
  • Application of acriflavine hydrochloride (Acriflavine) either as a bath or as a topical treatment
  • Heating the water to a temperature of 82 degrees Fahrenheit (28 degrees Celsius) for at least two weeks.

Prevention Of Ich In Cardinal Tetra

The best way to prevent Ich is by practicing good aquarium husbandry. And, this includes:

  • Maintaining proper water quality
  • Regularly changing the filter media
  • Quarantine of new fish for at least two weeks
  • Regularly performing water changes.


In conclusion, cardinal tetra (Paracheirodon axelrodi) is a small, colorful fish popular in the aquarium. Unfortunately, this species is prone to getting Ich, or white spot disease.

The good news is that several treatment methods are available for Ich in cardinal tetra. However, the bad news is that there is no cure for Ich, which can be fatal to the fish. Thus, the best way to prevent Ich is by practicing good aquarium husbandry.

Hopefully, this blog post has been helpful. For more information on Ich in cardinal tetra, don’t hesitate to contact us or visit other posts on this website.

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