first, symptoms:

the infected area forms a gray-white cotton wadding covering. The lesion site is round in the early stage, irregular patches in the later stage, and skin damage and bare muscles in severe cases. Gill tissue will also be invaded and infected, resulting in death.

Second, treatment

1. Formalin 1~25ppm, medicated bath for 1 hour.

2. salt (non-iodized salt is the best choice, because excessive iodine is harmful to aquatic organisms) 1~1.5% for 2~3 minutes. To make salt, coarse salt can also be used.

3. methylene blue 2ppm can get good results again the next day. Without changing water in time, the color of water will fade automatically. After 3 days, you can consider changing the water properly.