Fishes are prone to many diseases. Unhygienic conditions, lack of healthy food, carelessness, etc. also causes diseases in fishes. These fishes can be recognized easily. Unusual movements, drowsiness also are indicators of diseases in fishes. If the farming is done in a scientific way, the diseases can be kept at bay.
The main disease that affects the decaying of the fins. The symptoms are that fins start decaying gradually.The cure for this disease is to dip the fish daily for 2 minutes in dilute copper sulphate solution. Another disease that effect fish is the suppuration of gills. This disease is caused by a type of fungi called branchiomyces. If the disease is detected in the fish, fresh water should be passed into the pond. Also the affected fish must be transferred to another pond with fresh water. These fungi can be destroyed by putting lime in small quantities. Also this can be cured by dipping the fish in 5% saline solution twice daily for two minutes. If you observe black spots on the fish, then black spot disease can be confirmed. This is caused by small flatworms. This parasite reaches the water through aquatic birds or snails. If the presences of these birds or snails are restricted, or if they are destroyed, then the disease can be prevented. Also dipping the fish in Picric acid solution is a cure to this disease. Similar to black spots, fishes are affected with white spot disease also. White coloured boils and corpulence are symptoms of this disease, and is caused by a micro organism called ichthyophthirius.
Another disease that affects fish is the fish louse infection orargulus. By sprinkling lime into the water, this disease can be cured. Also by fixing bamboo poles in the pond, the fishes can rub their body on the poles and get relieved from the fish. Mix gamaxin at 0.2 PPM to destroy the lice. Anchor worm enters the skull of the fish and suck blood. The worms seen in the head has to be removed one by one and add potassium permanganate to prevent this. Similarly blood sucking leeches, nethobellydae also attack fish .Water has to be drained off completely from the pond and lime should be sprinkled so as to destroy such organisms. The best way to keep diseases at bay is to maintain good hygiene in the pond.