The fish body is rough and the scales are open, showing a loose ball shape. The scales are swollen at the base, and there is translucent or bloodshot mucus in the skin, which is often accompanied by hyperemia of the fin base, exophthalmos, hyperemia and ulceration of the skin, abdominal swelling, body inversion and upward abdomen.

Treatment: 1, soak the sick fish with 2% salt and 3% baking soda solution 10 minute, or soak the sick fish with 3% salt water10 ~15 minute.

2. First, crush the edema bubble of the scale capsule, scrub it with 10% warm salt water, apply tincture of iodine, and then inject 2 ml (0.4 g) of sulfathiazole sodium solution into muscle.

3. Add 5% chlortetracycline or oxytetracycline to the feed for 3 ~ 5 days.

These are all from books before.