Symptoms: The initial symptom is that small white spots appear on the pectoral fins and body of the koi, and quickly spread to the whole body. In the later stages, the surface of the body is covered with a white film, the mucus on the body surface increases, the color of the body is dark, the fish body is thin, slow swimming, often grouped in corners or reefs constantly rubbing, trying to get rid of the parasites. If the parasite is in the gills of the koi, it prevents them from absorbing oxygen, and even large fish sometimes die.

Origin of the disease and cause of infection: The pathogen is a kind of downy mildew worm named Cucumis sativus, which is suitable for breeding in water temperature of 15~25℃, and the development of the worm stops when the water temperature drops to below 10℃ or rises to 28℃.

Treatment:

In the early stage of the disease, the water temperature will be increased by 2~4 ℃, the sudden rise in temperature so that the death of the small melon worm, to achieve the purpose of curing without medicine.

If the water temperature is above 27℃ at the early stage, and the koi still suffers from white spot disease, in addition to adopting the method of warming up, you can also use the malachite green solution with a concentration of 0.05ppm or 2ppm methylene blue solution to medicate the fish body for a few consecutive days until the condition improves.