Agree with
Deadeye internal parasites. I assume it’s from the frogs, the insects wouldn’t carry parasites which spread to your fish. The frogs most likely carry fish lice or tapeworms, and since fish lice are external parasites, what I believe your snakehead has is some sort of tapeworm in it.
i ordered... not available for the moment ?
fish condition worsen seems his fins and scales are aff3cted see photo attached... do you guys think i can use permanganate ?
Fish that have not eaten for extended periods will pass a point beyond which they will refuse food, and cannot digest it even if they do eat. That's not even taking into account any underlying problems they may have that impacted their appetites in the first place.
Sorry to say, but I think your fish is well past that point, and is starting to show symptoms of secondary infections and problems. If it were mine, I would euthanize rather than prolonging its misery.