Bacterial rot of fins affects mostly aquarium fish, less often pond fish. Experienced aquarists know firsthand about this disease and can easily recognize it, and also know how to treat it. If you have not previously encountered this fish disease, we recommend reading our article.
Description of the disease
This disease has a bacterial origin and is very contagious. The main culprits of its development are the pathogenic bacteria Aeromonas punctata and Pseudomonas fluorescens.
Bacteria of the genus Aeromonas are anaerobic bacilli, that is, for their vital functions, both a small amount and a complete lack of oxygen are sufficient. Pseudomonas fluorescens — aerobic species of organisms, so oxygen is needed for their development, but some strains can use nitrates instead of oxygen. Regardless of the genus, both bacteria settle both in fresh water and in brackish.
A common sign of infection is red spots on the body and fins of fish. The disease without treatment progresses very quickly and leads to the death of the inhabitants of the aquarium / pool. Therefore, it is important to notice the first signs of infection in time and prevent its spread.
It is difficult to cure young fish, the mortality rate among them is high. Adult individuals recover more often, but their fins do not recover — they remain shortened with uneven edges, their rays with breaks and nodes. If the ulcers have passed onto the body, then most likely the individual will die.
Which fish get sick more often?
Aquarium fish are most often affected by fin rot. In the high-risk zone, fish with long and veil fins:
- scalaria;
- guppies;
- cockerels;
- veil tails ("goldfish"), etc.
Pond fish in cage farms can also suffer from the bacteria in question, but for them this disease is less common. According to our observations, it is young salmon that are susceptible to this disease. For them, adult sick individuals and their corpses are considered the source of infection.
Causes of the disease
The presence of pathogenic bacteria in the aquarium or pool is considered normal if their number does not exceed the norms and the conditions for keeping fish are not violated. The immunity of fish copes with bacteria that live in a reservoir, which does not make it possible for them to develop a disease. But everything changes when the number of microorganisms begins to grow or the fish immune system weakens due to poor care.
Factors affecting the development of the disease:
- Violation of the temperature regime. Each type of fish feels comfortable at a certain water temperature. The increased or decreased temperature of the environment in which the fish live can lead to shock in aquatic inhabitants and, consequently, a decrease in immunity.
- Stress in fish due to a sharp change in water parameters. If you replace a lot of old water with new water in an aquarium or start a fish in a reservoir without preliminary preparation, animals will experience severe stress, which can lead to a decrease in the body's ability to withstand diseases.
- Bad water parameters. A rare water change, rotting aquatic plants, water pollution, inappropriate pH values of the aquatic environment - all this is the reason for the deterioration of the health of fish and increase their susceptibility to pathogenic bacteria.
- Aggressiveness of fish. Barbuses, scalars, cichlids, gourami, etc. can inflict wounds on civilians and on each other when overpopulated. Carps are very voracious, and can eat smaller fish or injure young animals when trying to get more food. Open damaged areas and become sources of infection.
- Nutrition Intensity and Feed Quality. Feeding the inhabitants with “live” food is preferred, but vitamin-containing as well as plant-based food are also needed, so you need to alternate all types of food to provide the fish with a varied and complete diet. Improper feeding and overfeeding contribute to a decrease in immunity.
- Infected New Residents. When replenishing the number of fish, beginners must be quarantined or special additives (disinfecting + enhancing immunity) must be preventively added to the general water.
Symptoms
If a disease occurs in at least one individual, it is necessary to treat all the inhabitants who shared one reservoir with it. In order not to start the disease, regularly inspect your aquatic pets. The first signs are a bluish-white opacification of the edges of the fins, which was not previously observed. With the progression of the disease, the tips of the fins die off, then they are completely shortened or split into rays. Aquarists describe this disease as follows: “The fish seem to have“ decayed ”edges of the fins and seem to have a tail“ eaten up ”by someone, or“ The fish’s tail fin seems to have been torn apart and broken in some places. ”
The presence of a combination of the following symptoms indicates an advanced stage of the disease:
- red spots on the bases of the fins;
- ruffling of scales and its loss;
- possibly eye-eye, enlarged abdomen;
- fins are destroyed, erosion forms in their place (the risk of infection entering the blood is high, then the fish die).
In the acute course of the disease, the fish dies en masse, in the chronic course - it is possible to save the fish if adequate and timely treatment is provided. The disease should not be confused with the usual fin injury, mycobacteriosis or ichthyophonosis. About what other fish diseases exist and what their symptoms can be found here.
Treatment
At the initial stage, a regular water change of 30% of the total volume (every week) helps to cope with the disease, defended and heated to the maximum temperature values that are considered optimal for spawning of your particular fish species. When replacing water, the soil siphon, wash the aquarium filter, get rid of rotten plants. If this does not help, then more radical means are used, various substances and drugs are used.
Antibiotics
In a general aquarium or in separate bathtubs where a sick individual is placed, one of the following antibiotics is added:
- Bicillin-5 in the calculation of 5000 units / l of water. The necessary amount of antibiotic is dissolved in the bath, and “patients” are released there. The procedure lasts 30 minutes. Treatment is carried out for 6 days.
- Tetracycline (erythromycin is also suitable) at a dosage of 70-150 mg / l. Contribute to the general aquarium once a week for 2 months.
Antibiotics can be combined with antibacterial agents, such as streptocide. It is dissolved in a small separate container at the rate of 1.5 per 10 liters of water, and the solution is poured into the total capacity (i.e. if you have a 100 liter aquarium, then dissolve 15 g of streptocide in a jar and pour it into the aquarium).
Antibiotics should be added to the aquarium only as a last resort! Along with pathogenic organisms, they also kill beneficial bacteria, and this leads to a failure of biological balance in the aquarium, which in itself is not good for fish or other animals. Also note that some types of medicine are lethal to snails.
Potassium permanganate (potassium permanganate)
The potassium permanganate solution is used for medicinal baths. The concentration should be 1-1.5 g per cubic meter. m capacity. Fishes are kept in this solution for 10 minutes twice a day - in the morning and in the evening.
Other methods
In veterinary clinics you can purchase specialized tools for the treatment of fin rot: Sera Baktopur, TetraMedica General Tonic, Aquarium Pharmaceuticals T.C. Capsules, etc. When using drugs, strictly adhere to the recommendations in the instructions.
During treatment in a general aquarium, decor from plastic and ceramics is removed from it, enhance air aeration and reduce the amount of live nutrition. Each breed requires an individual approach. So, it is better to treat a scalar without depositing in separate baths, because with frequent transplants, the already fragile health of the fish can worsen. A rooster is recommended to be treated in quarantine.
The breeder of aquarium fish in his video shares how he treats his wards for fin rot:
Prevention
To reduce the risk of the disease, especially if you have fish breeds with beautiful long fins, follow a few rules:
- Change 30% of the water weekly to a new one while cleaning the bottom of the aquarium. Remember, adding water is not the same as replacing it!
- Feed your fish high-quality food, and do not overfeed.
- When buying new inhabitants, be sure to quarantine them for 10 days.
- Separate fish separately if in doubt about their health.
- Do not use other people's equipment and uncontaminated soil.
- Observe optimal fish keeping conditions.
- Add preventative medication to the aquarium water. Most often, basic violet K or malachite green (sold in veterinary pharmacies) is used for this purpose, however, when using these products, care should be taken and the prescribed dosage should be observed so as not to harm the fish.
So, fin rot is a dangerous and highly infectious disease. But with timely treatment, you can not only restore the fins to the fish, but also save the lives of most pets.