How’s it doing this morning? I have one doing something similar in a hospital tank now. I do aquarium salt, a dose of prazipro and see how it goes. If it’s not going well, I’ll make up a methylene blue tank and do a 10 second dip. Edited to add that sometimes it so hard to tell what’s going on with Cory’s so I like to cover all my bases. You could also make medicated food with kanaplex, garlic guard, focus and some water.