1. Reason: Goldfish mold may be caused by traumatic infection, and this mold is taken advantage of after goldfish surface injury. The early mold invasion will not be obvious, and the breeder will not find it until the wound grows white hair. But at this time, mold has entered the goldfish's body from the wound. If it is not treated in time, it will fester and malaise.

2. Treatment: Breeders need to fish out sick fish first to prevent them from transmitting mold to other fish. Then use potassium permanganate solution to give sick fish a medicated bath once a day for 20 minutes each time. During the treatment, the breeder needs to change the water once a day, but the amount of water changed each time should not be too large, and it should be controlled at one fifth of the total amount of water.

1. Reason: Goldfish mold may also be caused by bacterial infection, mainly because the water quality is too poor or the fed food carries bacteria. After goldfish has mold on its body, its expression will become decadent, and if it is serious, it is easy to rot.

2. Treatment: Breeders can install an ultraviolet lamp and turn it on for 4-5 hours every day, which can kill mold in water. Install a heating rod to raise the water temperature to about 25 ℃. High temperature can also inhibit the growth of mold and avoid the deterioration of the disease. Finally, malachite green solution is used to give sick fish a medicated bath once a day. After waiting for hyphae to fall off, goldfish will gradually improve.