Columnaris Vs. Ich: How To Distinguish Them?

Fish are prone to a broad range of diseases, some of which, if ignored, can be life-threatening.

The Columnaris vs. Ich controversy isn’t new in the fishkeeping world. However, novices may find it difficult to tell them apart.

Poor water conditions or overcrowded housing problems are frequently the roots of these illnesses.

If you are a beginner aquarist, this article will be helpful for you in distinguishing the two diseases so that you can apply proper treatment.

Let’s scroll down to get into details!

Columnaris Vs. Ich: Comparison Table

For a brief overview of the critical distinctions between Columnaris and Ich, let’s look at this comparison table.

  Columnaris Ich
Taxonomic Position Bacteria Protozoa
Causative agent Flexibacter columnare Ichthyophthirius multifiliis
Susceptible Species Freshwater fish: common carp, goldfish, grass carp. Young cultivated fish species.
Common Symptoms – Gray or white streaks or patches on the fins, skin, body, frayed fins, tails

– Lethargy

– Reduced appetite

– Higher mucus production

– Ulcers on the gills, fins, skin

– Fin rot

– Cotton-like look

– White spots on the fins, skin, or gills

– Higher mucus production

– Lethargy

– Reduced appetite

– Rubbing against the tank’s wall

Prevention – Filtering and changing the water frequently

– Regularly testing the tank water for nitrites, ammonia, and nitrates

-Regularly cleaning the substrate and filter

– Quarantining new species before introducing them to any aquarium

– Always maintaining clean water parameters

– Avoid overcrowding the tank

– Quarantining new species before introducing them to any aquarium

– Keeping your aquarium well-maintained and clean

– Maintaining suitable water environments

– Changing water regularly and controlling water parameters

– Increasing water temperature

Treatment – Antibiotics

– Tea tree oil

– Vinegar

– Natural or herbal therapy

– Anti-parasitic medication

– Aquarium salt

Symptoms And Treatments For Columnaris

Common symptoms:

Columnaris spreads quickly, making it crucial to identify it from many other fungal diseases. The following are some warning signs that this illness is present.

  • White scales
  • White, yellow, or orange patches on the body
  • Lethargy
  • Small patch near the fish’s dorsal fin
  • Rubbing against the tank’s hard surfaces
  • Falling-off scales
  • Reduced appetite
  • Turning white mouth or flaky-look

Symptoms of Columnaris


Having a quarantine aquarium available is the most fantastic way to stop Columnaris, given how widespread the illness may be.

A hospital aquarium helps prevent the spread of the infection to healthy species by allowing you to care for and cure sick creatures in an isolated area.

Additionally, it protects the healthy fish from any negative impacts of the treatments you must give the sick fish to get them back to normal condition.

Moreover, unwell fish are vulnerable targets for aggressive fellows and may experience bullying now.

You also need to pay attention to the water parameters in your tank if you want your fish to recover quickly.

Columnaris spread faster in warmer water. Therefore, always maintain the water in the hospital tank under 75℉.

It will be better if you gradually lower the water’s temperature. Any abrupt water changes will be harmful to your fish.

It’s great to lower the temperatures by no more than 2℉ after 60 minutes. After that, keep increasing until the temperature reaches the ideal level.

To track the fluctuations and maintain them under control, always use a water thermometer accessible.

For more complicated situations, it’s best to consult with experts or aquatic vets to get your fish correctly treated.

Treatments for Columnaris

Symptoms And Treatments For Ich

Common symptoms:

Ich-infected aquarium fish may exhibit particular signs, as with any infections. These are a few warning signs of this illness:

  • Swimming fish close to the water’s top
  • Rubbing or scratching against the hard surfaces of the tank
  • White spots on the fish’s body or around their gills
  • Lethargy
  • Loss of appetite
  • Hiding

ich symptoms


After you have detected the symptoms of Ich, you can apply various treatments to this illness.

You can choose natural or herbal therapies or antiparasitic medications. Think carefully, as the first option may harm other species in the tank.

The routine for caring for fish includes establishing and maintaining appropriate water conditions.

The first stage in the procedure is ensuring the water is sterile, oxygenated, and suitable for the kind of fish.

If you are a beginner and unsure how to perform water change for your tank, you can refer to this video:

This step involves checking ammonia levels or pH levels. The water temperature should not be over 84℉.

Be careful when adjusting the water temperature since your fish may suffer temperature shock when the temperature is beyond their thresholds.

You can treat Ich in your fish at home if you have knowledge of this disease and your fish species.

Otherwise, it’s best to talk to a professional aquatic vet instead of using over-the-counter medications.


What Are The Symptoms Of Columnaris?

If your fish get Columnaris infected, they may show these symptoms:

  • Gray or white streaks or patches on the fins, skin, body, frayed fins, tails
  • Lethargy
  • Reduced appetite
  • Higher mucus production
  • Ulcers on the gills, fins, skin
  • Fin rot
  • Cotton-like look

What Are The First Signs Of Ich In Fish?

You can notice white spots on the fish’s fins, skin, or gills as the first sign if they suffer an Ich infection.

Besides, you may see other symptoms, including

  • Higher mucus production
  • Lethargy
  • Reduced appetite
  • Rubbing against the tank’s wall

What Is Columnaris Caused By?

An aerobic bacteria called Flavobacterium columnare causes Columnaris in your fish.

Does Salt Cure Columnaris?

The short answer is yes! You can use 1 – 3 teaspoons of aquarium salt to reduce osmotic stress on fish from the damage to the fish’s epithelium caused by the bacteria.

What Temp Kills Ich?

The temperature rises aid in hastening the Ich lifespan, allowing for quicker parasite eradication.

If possible, raise your temperature to 86℉ or more; otherwise, 89℉ will be the maximum.

Don’t startle your fish. Instead, raise the temperature gradually after a few hours by 1 – 2℉.

Final Thoughts

Columnaris vs. Ich are relatively common diseases in fish. Hopefully, you know how to distinguish between these illnesses.

Although they may show similar symptoms, you can still notice and tell them apart, thanks to the critical signs mentioned above.

You will successfully treat these infections with our recommendations. Thanks for taking the time to follow us!