"Pseudomonosis" is an infectious disease of aquarium fish caused by specific bacteria of the genera Aeromonas, Pseudomonas, Flavobacterium (Flexibacter). It is characterized by the decay of the radial and interbeam tissues of the fins.
Pathogenesis. Aquarium fish of all species and age groups are sick, juveniles are most susceptible, the disease is often accompanied by its mass death. Adults also die. The pathogen of fin rot enters the aquarium with water, soil, aquatic plants and live feed taken from natural reservoirs. Fin rot occurs in fish, which are usually in a weakened state. Impact factors may be: changing conditions of detention, stress during transplants, conflict with other fish (especially biting fins), overcrowding, etc.
Symptoms. In sick fish, a slightly noticeable lowering of the edges of the fins appears, followed by their destruction and shortening.
In juveniles, the disease begins with the decay of the pectoral and caudal fins; in adult fish, this sequence is not noted. The initial sign of the disease is a bluish-white haze of the edges of the fins, then the ends of the rays fall away (in fry - caudal fins), torn, shuffled, rotted fins.
- Fin rot
Plaque, gray or white, uneven shaggy border.. With neglected forms - deterioration of the general condition of fish.

Fin rot
The last stage of the disease, in which fish death is observed, is characterized by the formation of white ulcers on the bases of destroyed fins. In sick fish, the duration of fin recovery depends on the degree of their destruction, the age of the fish, as well as the conditions for its maintenance and feeding. In earlier stages, the disease is easily treatable.
Diagnosis. Based on the data of history, clinical signs and laboratory methods of research. Fin rot must be distinguished from injuries and alkaline disease caused by the fact that in highly alkaline water the fins of fish shorten without visible damage, as if melting. In this case, it is necessary to normalize the water quality in the aquarium.
Treatment is carried out in a separate vessel (medical baths) and in a general aquarium if many fish are sick. The temperature should be raised to 28-30 degrees. Bacterial fin rot is treated with antibacterial drugs: Sulfur Baktopur, Sera Omnipur, Tetra General Tonik , Bicillin 5, Biseptol 480, Antibak , Furan 2, Doxycycline, etc.
Bicillin-5 Vial 1,500,000 units for the treatment of fish by a volume of 10 liters is divided into 6 parts, which corresponds to the full course of treatment. Fish are treated daily in baths for 30 minutes for 6 days. Each time fresh antibiotic solution is prepared (concentration is not changed).
Biseptol-480 is used in the form of dissolved powder tablets for 40 L. When using 5 l of water - 1/8 tablets. Treat for 7 days, every day a new solution is prepared in which the fish is aerated for a day.
The aquarium is disinfected with 3% chloramine solution; soil, fishing gear and fish-water equipment are disinfected by boiling, aqueous vegetation - with bicillin-5 solution.
The prevention of fin rot is reduced to preventing water, vegetation and non-neutralized soil from natural reservoirs from entering the aquarium, keeping fish in optimal conditions and maintaining in quarantine.