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As Betta fish keepers, we understand your concerns and frustrations. What follows is a closer look at Columnaris. From Columnaris’ path into your fish tank to treatments that will get rid of it, the information below will help identify Columnaris’ problems and protect your favorite Betta fish from suffering.
What are Columnaris Betta’s symptoms, and where does Comumnaris enter the aquarium? Can you take steps to prevent Columnaris Betta’s disease from happening in the first place?
Also referred to as Cotton Wool disease or Saddle Back disease, Columnaris is a fungal infection seen in the tropical fish keeping hobby (and is even more common in the commercial aquaculture markets). The Columnaris infection comes from bacteria, is easily spread, and is fatal if not treated.
Where Columnaris Betta disease comes from
The source of Cotton Wool or Saddle Back disease is the bacteria species Flavobacterium columnare. It is a common freshwater species that thrive in water in contact with cooler air (53 to 57-degrees Fahrenheit), including ponds.
Flavobacterium columnare is so common that it lives in most freshwater environments. That will include the water used to fill fish tanks, including your own.
The only aquariums that may lack the bacteria are those specifically treated for Columnaris disease. Those fish tanks will have Columnaris reintroduced into the water column with your next water change.
How Columnaris Betta disease spreads
If the bacteria already exist in your fish tank, why does it only affect fish under certain circumstances? How does a fish get sick with Columnaris? Usually, certain conditions trigger a Saddle Back disease outbreak, including:
Bio-loads higher than your filtration can handle
Overcrowding in your Betta fish tank
Lower levels of dissolved oxygen in the water column
A bio-load also refers to the nitrogen process in your aquarium. A contributor to the nitrogen process is waste from your Betta fish, as well as uneaten food. In fish tanks with multiple pets, decomposed remains can also be a source of increased nitrates.
For most hobbyists, a high bio-load may climb unchecked, as they usually keep only the Siamese Fighting fish in a tank. Betta keepers often use smaller aquariums where nitrate levels can affect water quality sooner.
Overcrowding can cause high bio-loads and lower oxygen levels in a fish tank, but it also increases stress levels. Over-stressed fish are more susceptible to things like the Cotton Wool disease.
A large number of fish for the space available is a primary culprit. For Bettas, that can cause them to chase other fish out of an established territory. Even with an appropriate number of fish for the water volume, a lack of hiding places or retreats can also increase stress levels (all the more during a fish fight), to the point that your Betta suffers from Columnaris.
Another factor that increases Columnaris infections is a lack of dissolved oxygen in the water column. Dissolved Oxygen (DO)enters your fish through its gills before entering its bloodstream.
Low DO is possible in small Betta aquariums, as owners sometimes fail to recognize the problem. Siamese Fighting fish have a Labyrinth breathing system that allows them to receive oxygen through the air. Maintaining proper water conditions and adding aeration or live plants can increase dissolved oxygen levels.
Can Columnaris infect an already sick Betta fish?
Yes. Outside of the conditions mentioned above, current and previous bacterial infection sites can introduce Saddle Back disease. Current bacterial infection sites are more susceptible, but previously damaged gills, fins, or scales are also accessible.
Bacterial growth from Columnaris might look like another type of infection, so proper identification will allow you to treat it properly.
What Does Columnaris Betta Disease Do?
The Cotton Wool disease destroys live tissue in different areas of your pet’s body. It can result in actual loss of epidermal material and can manifest as cloudy patches. Saddle Back disease can also create mucus around the gills and head of your Betta fish.
Several locations can be affected, with damage that includes:
The disease often starts on your fish’s fins, causing them to fray into pieces. A ragged appearance to your pet’s tail fin will usually occur before the dorsal or other fins are affected.
Mucus can build up on the gills, and they can become discolored. As the infection grows, the gills will become damaged, causing the Siamese Fighting fish to breathe rapidly.
Ulcers can appear on your pet’s body, with a white or cloudy appearance to them. Advanced bacterial growth will result in the loss of skin in the area of these wounds.
How do Columnaris symptoms affect your Betta fish?
Fin damage can make it difficult for you Betta to move around its tank. That can also prevent it from swimming upright, and the result will be a fish that swims on its side or even upside down.
Gill damage and mucus build-up will force your pet to have labored breathing. The gills will flare, and the fish will look like it is gasping for oxygen. You may notice your Siamese Fighting fish moving to the surface and dipping below it as it seeks to breathe normally.
Open wounds on the skin will promote the growth of the fungus. As it grows, the epidermal material will be lost. It will eventually break down your Betta’s ability to fight the infection.
Is Columnaris Betta disease fatal?
The Cotton Wool disease can ravage your pet’s body, becoming fatal quickly. Water conditions, age, and stage of disease all play into how long it will take to kill your Betta fish.
If left untreated, Columnaris can kill your fish in two or three days. It takes one or two days to develop the ulcerations or other symptoms you can notice, giving you a small window to treat and save your Betta.
Columnaris can be fatal, even with treatment. It will depend upon the damage done to the betta fish before you intervened.
How To Treat Columnaris In Betta Fish
If you suspect a Columnaris outbreak in your Betta tank, the first thing you need to do is quarantine your fish, if possible. A hospital tank is a great accessory to have and will allow you to medicate the water quickly. If you do not have a hospital tank, you will have to treat your whole Betta aquarium.
Use a water-testing kit to verify the parameters in the water column. You may discover conditions that are promoting Columnaris growth or affect medications used for treatment.
How to treat Columnaris in Betta fish:
Isolate sick fish
Check water conditions
Select one or more treatments
Reintroduce treated fish once done
Most hobbyists and veterinarians will suggest treatments that include antibiotics such as Nitrofurazone and Kanamycin. Several products are commercially available for treatments, such as:
Seachem’s KanaPlex: One dose every 48-hours (Three-dose cycle)
API’s Furan 2: Two does within 24-hours, twice (Four-dose cycle)
Furan 2 contains Nitrofurazone, and KanaPlex contains Kanamycin. You want to use a commercial treatment with either, as they fight several fungal infections, including symptoms of Columnaris.
Medicated baths will allow the fish to absorb the treatment at the point of infection and internally. These treatments can also include freshwater aquarium salts that eliminate Columnaris.
Treatments will extend for several days and will require partial water changes during that time. Follow the instructions on the label for exact procedures.
If you isolated your fish in quarantine, you need to prepare your aquarium for its return. If there was a high level of nitrates, a water change is required. Make sure you have plenty of aeration to promote oxygen content in the water column.
Once your Betta fish has been treated and has recovered, you can reintroduce it into the aquarium. Make sure that it has plenty of room and hiding places as it returns home.
How To Prevent Columnaris In Your Betta Fish Tank
There are several steps that you can take to prevent Columnaris outbreaks to begin with:
Establish a proper nitrogen cycle
Test water conditions
Keep tank clean
Do frequent water changes
Don’t overstock your aquarium
Isolate new fish
Inspect fish daily
An established and balanced nitrogen cycle will allow you to maintain an acceptable bio-load in your Betta fish aquarium. New tanks need cycling before introducing fish.
Get a quality water testing kit that allows you to check multiple parameters. The more information you have about the water chemistry, the better water conditions you can provide for your pets.
Keep your tank clean. Make sure to remove dead fish or larger chunks of debris with your hand, net, or vacuum.
Change your aquarium water regularly. Maintain a consistent schedule that allows you to change 25 to 50-percent of the water, depending upon your aquarium’s needs.
Don’t overstock your aquarium. Follow the one-inch of fish per gallon rule at most. Remember that Betta fish are territorial and aggressive, so provide hiding spots for all tankmates.
Isolate new fish for a few days before introducing them into your established tank. It will make treatments easy and prevent contamination of your current stock.
Finally, inspect your Betta fish daily. Columnaris moves quickly, so fast identification is key to survival.
Columnaris Betta FAQ
Is Columnaris transferable to humans?
No. Fortunately, Columnaris is not zoonotic. Like many other fish tank bacteria, it can not jump from your Betta fish to a human.
It is, however, highly contagious between tropical fish, including your pet Betta fish. Older fish, fish under stress, and Siamese Fighting fish with current bacterial infections are at a higher risk of contacting Columnaris from other tank mates.
Can Columnaris go away on its own?
No. Saddle Back disease is fatal if left untreated. In many cases, your fish will die before you are even aware that there is a problem. Betta fish will die from the Cotton Wool disease within 48 to 72 hours from developing the first symptoms.
You will have to treat your fish to save it. It may still die, even if you medicate it.
How long can a fish live with Columnaris?
The disease spreads quickly and often kills your fish before you are aware that there is a problem. Columnaris will manifest symptoms within one or two days. It is fatal within two or three days, making quick treatment critical.
How long does Columnaris live without a host?
The Flavobacterium columnare found in freshwater can live over 30 days without a host. That allows it to potentially live in your fish tank a month after adding water.
Older water, or treated water, will lack the bacteria. The maximum length of time Columnaris lives in water without a host is 35 days.
Why does my Betta look fuzzy?
The “Fuzz” that you see on your pet is a sign of a fungal infection. It could be Columnaris. The condition could also be from other pathogens besides Flavobacterium columnare.
Luckily, treatments are similar for many of these diseases, allowing you to treat a host of fungal infections with the same medications.
Preventing Your Betta Fish From Feeling Funky
While Columnaris is fatal, you can treat it if caught early enough. Products like Furan 2 or Kanaplex will help your Betta fish fight the infection. As with most fish diseases, prevention is more manageable than treatment.
Provide your pets with:
Good aquarium and water conditions
Safety precautions such as isolating new fish and daily inspections
A stress-free environment
Proper medications quickly and efficiently
Is there a question that you may have or suggestions you would like to offer? Please comment below so that we can answer them or continue the conversation!
Last Updated: January 25, 2022
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