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Columnaris in guppy is a contagious gram-negative bacterial infection. Many expert fish keepers are even afraid of columnaris disease.
| The best approach to deal with columnaris in guppy is to provide optimal water quality, keep the water temperature low, ideal tank condition, prevention and treating with right medication to help fast recovery. |
In this article, I will discuss the causes, signs, cure, and prevention of columnaris in guppy fish.
Quick Look On Columnaris In Guppy
Table of Contents
What Is Columnaris in Guppy Fish?
Columnaris is a common disease found in freshwater fish (Guppy Fish).
Many fishkeepers also refer to columnaris as cotton wool disease, cotton mouth disease, and saddleback disease. It is the same disease which has different names, so don’t get confused by names. Columnaris in guppy are often wrongly identified as fungus infections.
Hence, it is important to understand what is columnaris in fish.
Flavobacterium columnare is an aquatic bacterium that causes columnaris in fish. It is an important microorganism present in freshwater but affects those guppy fish with weak immunity and under stress, which induces columnaris in guppy.
| This bacteria is a long rod shape that looks similar to a column, hence named columnaris. |
There are two kinds of columnaris:
1. Acute Columnaris Disease
Guppies can get attacked by this bacteria so fast without showing any clear symptoms. Guppies immunity system is damaged and the fish can die within 24 hours. Further, there is a high chance of fish tank mates dying as it spreads quickly.
2. Chronic Columnaris Disease
Guppy fish have various symptoms. This columnaris attacks multiple body parts of guppy fish like lips, fins, gills, and skin. Even if the bacteria is slowly growing can cause death if not treated on time.
“Can columnaris spread to humans?” – No, columnaris cannot spread to humans. These bacteria struggle to grow in human body temperature.
What Causes Columnaris Disease In Guppy Fish?
As discussed, columnaris is always present in water tanks but only triggers when guppies are under stress and have poor immunity levels. Many hobbyists have a question “How do fish get columnaris?”
I will discuss the reasons that cause columnaris in guppy fish:
1. Irregular Aquarium Maintenance
Regular water changes and basic care of guppy fish tank help provide a stress-free and healthy aquarium environment for guppies.
A weekly change of 25% tank water will clean fish waste, uneaten food, decaying plants, and other debris. A good filter helps in keeping the aquarium clean.
When the tank water is not maintained then it forms harmful bacteria which makes guppies sick with columnaris.
2. Overcrowding Guppy Tank
The thumb rule is one inch of guppy fish requires one gallon of water. If not followed leads to overstocking.
Too many guppies in small tank leads to overcrowding the tank which leads to water pollution, weakens immunity and creates stress. In this situation, the efficient filter will not work properly and not clean the waste in your guppy tank. The waste builds up toxins.
When there is not enough space to swim in a tank it stresses guppy and is likely to get columnaris in aquarium fish.
3. Fluctuating Water Temperature and pH Level
The sudden fluctuation in water temperature decreases guppies lifespan.
When the water temperature falls below minimum or exceeds the maximum limit, guppies feel stress which weakens their immunity.
It is equally important to measure pH range on regular basis to check whether water is acidic or alkaline. You can use a digital pH meter, pH test strip and pH test kit.
Due to these stressful conditions, guppies can get sick very often which makes them vulnerable to diseases such as columnaris.
To stabilize the water temperature, it is recommended to use a water heater in your guppy fish tank and a simple way to achieve the best water pH for guppies is to change water every week.
4. Insufficient Diet
A balanced diet is essential for the overall growth and well-being of guppies.
The lack of a nutritious diet will weaken their immune system which leads to diseases such as guppy columnaris.
The best food for guppy fish includes fish pellets, worms, fish flakes, insects, and frozen or live foods like brine shrimp or daphnia. This top-quality fish food is designed to ensure the specific nutrient needs of guppies.
5. Incompatible Tank Mates
Before adding other fish to fish tank, you should properly evaluate whether tank mates are suitable for guppies or not.
If guppies are kept with aggressive tank mates, then they are always under threat of being harassed or bullied. This increases stress levels in guppies which makes them avoid food, being scared, and disturbed sleeping patterns.
In case of a territorial fight, guppies may cause injuries that weakens immune system and there is a risk of bacteria entering their body through sores or cuts on the skin. This causes columnaris in guppy.
6. Transportation Stress
It is hard for guppy fish when being shipped from a pet store or local shop.
The trip is stressful and the water parameters in their new tank will be different from the old pet store fish tank which increases anxiety and prone to columnaris disease guppy.
The best solution to ease this transition is acclimation.
You can float the sealed bag on top of fish tank for 20-25 minutes, gradually bag adapts water temperature then you can open seal of a bag which allows guppy fish to enjoy new home. This method helps guppies to adapt to new water parameters.
7. Infected Guppy Fish or Equipment
When you buy guppy fish online or from a pet store, then there is a high chance of buying infected fish which can bring in contagious diseases like columnaris with it.
A common practice that should be followed is to quarantine new guppies before adding to the main tank, this prevents columnaris from spreading and prevents other tank fish from falling sick.
If your guppy is sick and you moved it to hospital tank, then avoid using the same equipment in both tanks (main tank and hospital tank). As there are high chances of infection spreading to main tank fish.
After understanding the causes of columnaris in fish, it is important to look for signs of columnaris in guppies.
“Is columnaris contagious to other fish?” – Yes, columnaris is contagious to other fish and spreads quickly in your guppy fish tank.
You can save a dying guppy fish when diagnosed at an early stage. With correct medication and simple tank maintenance, you can treat columnaris in guppy. If columnaris are not treated on time then guppy fish may die.
What Are the Symptoms of Columnaris in Guppy Fish?
Guppy columnaris symptoms are puffy lips, white spots, damaged fins, and infected gills. Hence, it is hard to know because it looks similar to other guppy fish diseases.
Columnaris in guppy are often confused with fungal infection due to fungal-like growth.
You might think “How long can a fish live with columnaris?” – Guppy fish can survive with columnaris depending on immunity level, stage of infection, tank condition and type of columnaris.
The most common question asked on social media is “How do you identify columnaris in guppy fish?” You should quickly look for these signs which will help to save a dying guppy fish.
1. White Spots on Body
When a guppy is sick with columnaris, the first symptom you can notice is pale, yellow, whitish, orange or greyish fungus-like growth forms on the body. The patch color depends on potency of infection and guppies body color.
As columnaris disease advances, you can see cotton-like spots on different parts of the body such as near the mouth, head or gills. Hence it is called cotton wool disease or cotton mouth disease.
When cotton wool disease is not treated, it becomes more critical. The faded patch swells which further extends to the skin and scales fall off. In some cases, muscles come out and red bloody patch stain grows.
This bacterial infection appears like long threads on the skin which gets mixed up with fish fungus.
When you see any of these signs immediately contact fish expert for treatment.
2. Frayed Fins
The noticeable guppy columnaris symptoms are their fins worn out and the edges of scales affected, but often confused with fin rot.
Gradually, fins become weaker and you might notice problems on the bottom of the fin.
The disease earns its name saddleback disease as the discolored patch forms on dorsal fin of guppy fish which looks like horse saddle.
3. Slimy Mucus
You will notice chronic columnaris symptoms in fish like a slimy mucus on its mouth, gills, back and head. The reason is that guppy fish natural immunity is fighting self-recovery.
Sadly, columnaris is powerful for guppies immune system to defeat on its own.
4. Brown Gills
You will observe columnaris on guppies gills which turn brown. The decaying and dying of inner cells is the cause of browning gills. At this point, it is hard to treat columnaris in guppies.
In some cases, there are no visible signs of infected gills because the infection is still inside the gills and not reached outside. Due to this, your fish will behave unusually like breathing heavily and fast and guppies gasping at top of tank for more oxygen.
5. Swollen Mouth
In columnaris guppy fish mouth appears swollen, scaly, and discolored. This infection spreads internally and externally.
6. Scratching
When you spot guppy fish rubbing against things, then there is an infection on the skin. So, this can happen at any phase of columnaris disease.
To soothe discomfort and itching guppies keep on scratching which leads to increased dryness, ulcers, sores, and even tears of fish skin.
7. Other Columnaris Symptoms
The additional symptoms of columnaris in fish are laziness, hiding, appetite loss and not meeting other tank mates. In severe cases, guppies can even get infected by other diseases all because of low immunity.
How To Treat Columnaris In Guppies?
One of the most common concerns fish lovers have is “Can columnaris be cured?” – Yes, your pet guppy fish can be saved if columnaris is diagnosed in an early stage and given proper treatment.
Once you recognize guppy columnaris symptoms, you can treat it at home if it is in an early stage of sickness but if the disease has advanced you should consult a veterinarian.
Other aquarists may think “How long does it take to treat columnaris?” – It takes 1 to 2 weeks to treat columanris guppy.
So, what is the best treatment for columnaris? The following step will assist in columnaris guppy treatment.
Step-1 Quarantine Sick Guppy
You should start by moving the sick guppy fish to a hospital tank. Isolating sick fish has some advantages.
– Initially, this prevents spreading of columnaris disease to fish in good health.
– Next, the unwell guppy is kept away from stress and harassment from other tank mates.
– Lastly, when you treat sick guppies in the main tank, you use more medication than required which is on the one hand harmful for healthy guppies and on the other hand it is expensive.
Avoid using main tank water in hospital tank as water might be contagious. You should perform a water test.
Step-2 Measure the Water Quality of the Hospital Tank
The water quality impacts well being of sick guppy fish. So, you should test the water parameters using the API Master Test Kit. While measuring ammonia, nitrate, nitrite and pH levels ensures the desired range is achieved or not.
When the ideal level is not attained can elevate stress in sick fish and decrease immunity levels against columnaris.
Step-3 Lower the Water Temperature in Quarantine Tank
Columnaris spreads faster and is more dangerous in warm water between 85°F–90°F(29°C-32°C).
So the most obvious question is What temperature should I treat columnaris?
First, use a thermometer to check water temperature, in case of high water temperature start lowering tank temperature to 75°F (24 °C) and try to reach 72°F (22 °C).
You should change slowly the water temperature to avoid shock and stress. So, every hour decrease 1°F and observe how sick guppy is adapting to this change.
Step-4 Medication
You must treat columnaris in guppies with a medicated fish bath and medicated food which soothes fish pain externally as well as internally.
Treating columnaris with Kanaplex and Furan-2 will help guppies to heal and fight against disease. Before giving dosage always refer to the instructions mentioned on the medication. For effective medication remember to take filter media out of the tank.
Consult Vet before any medication.
You need to wait for a week without performing water change.
If you see guppy fish recovering, after a week, do partial water change.
In extreme cases, if guppy is still unwell give a second dosage of medication and wait for another week.
When to Return Guppy Fish to Main Tank After Columnaris?
Before adding guppy from hospital tank, you must ensure that the main tank is treated for columnaris and there is no infection present.
For your information, columnaris can live till 2 months even without any fish in tank. Use the same medication dosage in main tank as used in a quarantine tank for one month. You can use a bacteria booster as Kanaplex harms nitrifying bacteria.
At least for one month, you should quarantine sick guppy fish and before reintroducing guppy fish to main tank check whether the water parameters are ideal.
How Do You Prevent Columnaris In Guppy?
Preventing guppy fish from columnaris is the best approach rather than treating them. There are some effective methods for columnaris prevention:
1. You should perform 25% water change every week.
2. Do weekly cleaning of aquarium by removing uneaten food, fish waste, dead plants and fish.
3. Lowering general hardness (GH) of water makes it hard for columnaris to survive.
3. Avoid overcrowding the fish tank by following the simple rule that 1 inch of guppy fish requires 1 gallon of water.
4. Keep guppies with compatible tank mates to avoid fish rivalry and injuries.
5. A balanced diet should be given to maintain good health of guppies.
6. Follow a practice to quarantine new guppy fish before introducing to main tank.
Conclusion
Columnaris are there in all aquariums but triggers when guppies are in stress.
Columnaris in guppy are difficult to recognize as many symptoms closely match with other diseases. Your early action can help guppies to recover faster.
Prevention is a good way than to find a remedy. Maintain ideal water levels and give required treatment to columnaris guppy.
For any queries, please feel free to ask in the comment box.
Happy Guppy Keeping!
FAQS
Can fish survive columnaris?
Yes, fish can survive columnaris relies on aspects like early detection of disease, best water parameters, good immune system, stress-free environment, healthy tank condition, nutritious diet and isolating new as well as sick guppy fish.
Can salt cure columnaris?
Yes, salt can cure columnaris.
Is Columnaris treatable?
Yes, columnaris is treatable only when quick action is taken by giving medication and timely detection of disease.
I am Alexa with 5+ years of experience in fishkeeping industry with expertise in taking care of guppies, aquariums, and dealing with diseases. Moreover, I am lovely wife, dedicated mom, and passionate guppy fish keeper. If you are into guppy fish keeping like me, you are in the right place. Explore the blog, ask questions, and enjoy guppy fishkeeping journey with GuppyAdvisor.
