1. Reason: Water mold is a common disease of mermaid, which is mainly due to poor water quality. There are many harmful substances in water, which will cause a large number of bacteria to breed, resulting in water mold.

2. Treatment: Water mold is contagious to some extent. Breeders need to isolate sick fish immediately after finding them to avoid infecting other fish. Then use potassium permanganate solution to give sick fish a medicated bath once a day for about 15 minutes each time. In about a week, the sick fish can be cured.

1. Reason: One eyebrow mermaid is also prone to white spot disease, which is mainly caused by too much change or too low water temperature. They are tropical fish. When the water temperature is low, their resistance will decline, and they are prone to white spot disease.

2. Treatment: The breeder needs to raise the water temperature to 26 ℃ immediately. In the high temperature environment, the growth rate and activity of bacteria will decrease. Then use Baidianjing to take a medicated bath for the sick fish, and stick to the medicated bath for 3 days, and the sick fish can recover.

1. Reason: One-eyebrow mermaid is also prone to enteritis, and they don't feel full. If they feed more food, they may have indigestion. In addition, the food fed by breeders is miscellaneous, which is easy to breed bacteria and suffer from enteritis.

2. Treatment: If the mermaid can still eat, the breeder can feed them some probiotics or furazolidone. If they can't eat, they can put furazolidone in water and give them a medicated bath.