What is the white spot on the map fish? How to treat it more effectively?

If it's leukoplakia! In a few days, I will find that it is not just on the fin! It's systematic.

Let's talk about prevention: white spot disease is one of the most common parasitic diseases of fish, which mostly occurs in the season of low water temperature in late autumn and early spring, and tropical fish of CYPRINIDAE and Cicadellidae are more susceptible to infection. White spot disease is also called gourd disease. The body of Cucurbitaceae is spherical and covered with cilia, with a diameter of about 0.8mm, which is a small white spot visible to the naked eye. At the water temperature of 18-23℃, melons often parasitize under the skin, caudal fin and gills of fish, absorbing nutrients from fish tissues and stimulating fish to secrete a lot of mucus, thus forming white pustules on the surface of fish and spreading all over the fish. When tropical fish suffer from this disease, first of all, white spots appear on the fins, and the fish appear to be slow to move, floating on the water and rarely moving. Or often swim sideways and tickle quickly next to water plants and gravel. In severe cases, the fish will grow full of white spots, stop eating, lose weight, have difficulty breathing and even die. The course of disease is usually about 5~ 10 days. Because cucurbitaceae plants are not resistant to high temperature, they generally stop developing above 25℃ and die naturally when the water temperature rises to 28~30℃. Therefore, for tropical fish with white spot disease, the treatment is not too troublesome. As long as the water temperature is kept at about 28~30℃, all the cysts on the fish body will fall off after one week. If drug treatment is supplemented at this time, the effect will be better. When taking medicine, 0. 1ppm mercurous nitrate can be used as a medicinal bath in the fish tank. For seriously ill fish, 2ppm mercurous nitrate or 0.5ppm malachite green solution can be used to invade and wash the sick fish for 2-3 hours. When the symptoms of sick fish disappear, fresh water should be replaced in time to avoid fish mercury poisoning for too long. To prevent this disease, just keep the water temperature above 25℃. When introducing new fish, it is generally possible to prevent the occurrence of white spot disease by soaking it in potassium permanganate solution or salt water for disinfection and then putting it into a fish tank.