What's wrong with grass carp?

The body surface of grass carp in my cage is rotten and red and swollen and scaly, the internal organs are in water, and the black membrane in the belly of the fish is rotten. I would like to ask what kind of disease this is-- decayed skin disease or grass carp hemorrhagic disease all have similar manifestations, but I feel more like grass carp hemorrhagic disease. It depends on the specific performance of your internal organs. If only there were pictures.