What Causes White Spot in Fish and How To Treat It?

white spots in fish

One of the most common parasitic infections noted in ornamental fishes is Ich. The parasite responsible for the condition is a protozoan, Ichthyophthirius multifiliis. This disease can be contagious. The parasite appears as a white spot on the skin and fins. It also damages the gills of the fish, thereby resulting in respiratory disorders. Infections of Ich appear with fluctuations in water quality and temperature. Yet, Ichthyophthirius multifiliis is not the only parasite responsible for white spots in fishes.

Several microbes can give rise to white spots in fishes. Sporozoans and Lymphocystis also cause a large white spot on fishes. Aquarists have also found a new genus of microbe, Neoichthyophthirius schlotfeldti. They believe that it also contributes to white spots on fishes. 

White spot in fish due to Lymphocystis Virus 

Lymphocystis is a common viral disease in both saltwater and freshwater fish. The virus responsible for the condition belongs to the genus Lymphocystivirus. Whenever a fish is in stress in a new environment, this virus is believed to grow at a rapid pace. The fishes start developing small white pin-prick growths on their skin. This is not Ich. Soon, you will notice the formation of clumps. They appear more like cauliflower-like growth on fins, mouth, skin, and gills. 

Lymphocystivirus starts appearing at different locations as lesions. This complicates the early diagnosis done. These viruses do not show any kind of host specificity. Currently, there is no cure for this virus. Privately owned fish breeding and research facilities in Florida have researched this virus. They have developed a special treatment using the drug acyclovir. The researchers injected acyclovir into the fish tank for two days at the rate of 200 mg per 10 gallons. They noticed tremendous improvements in the condition of the fishes. 

Some aquarists also suggest surgery for removing the affected area. They also recommend trying an antibiotic bath after the surgery. This will prevent the chances of any secondary bacterial infections. As of now, there is no simple cure for the treatment of Lymphocystis. If you neglect the condition, then the virus will inhibit the ability of the fish to eat, breathe, and swim. The secondary infections will also play their role and will lead to death.

How to treat white spot in fishes due to Lymphocystis?  

There is no cure for the infection from the Lymphocystis virus. The best cure can be to provide your aquarium fishes with a stress-free life. You can do a bacteria treatment weekly. This will kill any bacteria present in your aquarium environment. If the condition is not severe, then your fishes will heal slowly. The entire process may consume months. No matter what the situation is, the first outbreaks are quite difficult to deal with. This is because the immune system of your pet fishes needs to learn how to suppress them.  

Lymphocystis appear on fishes are white or beige colored nodules. These also result in the Popeye condition in fishes. This is because of the infected tissues behind the eyeball swell. This causes the eye to protrude. The condition worsens as the infection progresses. Currently, prevention is the only way you can tackle this condition. 

Indications Treatment Prevention
Contagious and spreads to other fishes There is no cure for this condition Close examination of fishes that have been purchased from pet stores
The virus enters the body of fishes through openings due to injuries or wounds The virus spreads like cancer throughout the body of the infected fish Avoid subjecting the fishes to stressful environments
Spreads rapidly Scientists at National Fish Pharmaceuticals recommend surgical removal of growths Quarantine new fishes and treating secondary infections immediately
Death occurs due to secondary fungal or bacterial infection Quick identification and prevention would be the best move Feeding a nutritional diet

The best treatment for white spots in fish 

There is no best white spot treatment for tropical fishes. You should focus more on sterilizing the tank often. In case of any secondary infection, you must act immediately. You can use sodium hypochlorite, potassium permanganate, and formalin to kill the microbes. Treating Lymphocystis is like treating any other contagious disease. There is no proper cure. But, you can try exercising care. Also, take precautionary measures for preventing the condition.

White spot due to Cryptocaryon irritans 

There is another causative agent that results in white spots in fishes. Cryptocaryon irritans is a large ciliated protozoan. It results in white spots like Ich. This disease occurs in marine fishes. But, it can also occur in freshwater fishes. Infection caused due to this parasite can result in significant problems for aquarists. The parasite affects the epidermis of the gills, fins, and skin.

Cryptocaryon irritans results in Ich like symptoms in marine or saltwater fishes. Hence, the condition caused is known as marine Ich or marine white spot disease. The symptoms noted are similar to that of Ich in freshwater fishes. There are significant white spots on the body of the fish. Cryptocaryon irritans spends a longer time while encapsulated on the skin. The infected fish may have white patches, nodules, or spots on gills, fins, and skin. Also, you will note changes in skin color, increased production of mucus, pale gills, and cloudy eyes. Moreover, infected fishes may swim abnormally, hang at the surface, or act lethargic.

The best thing to do would be to quarantine the infected fishes. Treatment with copper solutions and formalin can be beneficial. You can also use quinine formulations. If you have other creatures in the tank, such as corals and invertebrates, then the treatment may become difficult. Hence, it is best to quarantine the fishes that have developed white spots. 

White spot in fish due to Posthodiplostomum minimum 

Digenetic trematodes usually plague fishes in water ponds. These do not pose a major threat to health immediately. But, they do result in undesirable conditions. Posthodiplostomum minimum microbes are also called as white grubs. These are nothing but internal parasites. These have complex life cycles. Besides fishes, these parasites also affect aquatic snails. 

White grubs appear as small white cysts in the flesh of the fish. The aquarists often overlook these. They live in and around the fishes. The grubs affect the internal organs such as the heart, liver, and kidneys. They also settle in connective tissues. These parasites reproduce in guts of aquatic birds such as herons. The eggs pass on to the marine fishes through feces. The eggs hatch in water within a short period. This ends up infecting the fishes. 

White grubs end up destroying the entire organs. These can also result in bleeding if the infection is severe. They rip through flesh and end up deforming the organs. They also impair the immune functions in the fishes. Further, this increases the chances of developing secondary infections. 

Preventing white grubs 

No matter what the condition is, prevention is always the key. If you have aquarium ponds, then you need to take special care of grub infections. Once the condition turns severe, you would not be able to do anything for your fishes. Hence, avoidance is essential. Avoid fish-eating birds and snails if you have an aquarium pond. Make sure to check the source while purchasing fishes. You need to quarantine new fishes before adding them to your main aquarium tank. 

White spot in tropical fish due to Columnaris disease 

You must have now learned that Ich is not the only condition that results in white spots in fishes. You need to understand what causes white spots in fishes. It is only then you can find an effective treatment. White spots in fish can also be due to Columnaris. It is a bacterial infection that can be both internal and external. This is often mistaken for a fungal infection because it results in mold-like lesions. You can treat this condition with basic maintenance and antibiotics. 

Columnaris is a common bacterial infection in aquarium fishes. The name is due to the columnar shaped bacteria resulting in the condition. This bacterium is present almost in all aquarium environments. Hence, you need to make effective use of antibacterial solutions. This disease is also known as cotton mouth disease and guppy disease. Some aquarists call it a saddleback disease or cotton wool disease.  

Symptoms of Columnaris in fish 

The symptoms are usually noted in fishes with Columnaris are lesions. In severe cases, the lesions spread rapidly. These can wipe out a large number of fishes within hours. The condition accelerates when the water temperature is high. The infection presents itself with grayish or white spots. You can also notice patches around the gills or fins. The lesions have a shiny appearance. They tend to become brownish or yellowish as the infection progresses. 

The lesions around the mouth appear cottony or moldy. The bacteria eventually eat away the flesh around the mouth. The fins get eroded as the condition progresses. If the infection takes an internal course, then you will not notice any spots on the skin. It will be hard for you to identify the cause of death if the infection is internal. 

Causes of Columnaris 

Columnaris bacteria mostly affect fishes in stressful aquarium environments. Inadequate diet and poor water quality can add to the stress. Incorrect handling while shipping can also lower immunity. This bacterium can enter fish through small wounds on the body. This disease is contagious. It also spreads through contaminated food, specimen containers, and nets. This is why you should use sterile techniques. 

Treatment of Columnaris 

You can treat external infections with the use of antibiotics. You can also use Terramycin, Furan, Acriflavine, and copper sulfate in the water tank. Terramycin is quite effective for both internal infections. Also, you can use it in an antibacterial bath. 

You can lower osmotic pressure by adding salt. This will be helpful for fishes with damaged epithelium. Also, adding salt can benefit livebearers. Catfish are quite sensitive to salt. Hence, you need to be careful while treating them.   

Preventing Columnaris 

The best thing to do is to prevent the outbreak. This can be done by regulating the internal conditions of the tank. You should change the water regularly. Also, maintain the environment clean. You can also vacuum the gravel. Maintaining a proper diet is also essential. Place new fishes in quarantine tanks. This will prevent the spread of the disease upon infection. Disinfect specimen containers, nets, and any other aquarium equipment. You can make use of commercial preparations such as Net Soak or Net Dip. These are for disinfecting nets and decoration items.

To know more about different Saltwater and Freshwater Aquarium Fish Diseases, click this article “Aquarium Fish Diseases: Causes, Symptoms, and Treatments“.