Angel fish sick need help id problem pics posted

Woke up this morning and took a peak at the tank before I went to work and my male watanabe angel looked like he had a bunch of cuts going up and down his body near his head. Turned the light on and has a patch on his body that looks like his scales are flaking off if that makes sense. He is hanging out in the rocks which is not like him and just noticed this morning, did not see this on him yesterday, pics below any help would be hugely appreciated!

 

any other info needed please let me know.

 

have you seen him scractch himself in objects?
what are your water parameters?
size tank?
is he eating?
any odd behavior? other than hiding?

 

dead fish

 

from the picture, that almost looks like a burn. in person, does it look like a burn or something growing on the fish? is it possible for a fish to burn themselves on a heater? i have never heard of that happening but........

 

looks kinda like a fungus brought on by lack of slime coat (most probably stress, poor water quality??) then a scratch then onset of fungus infection. pictures arent entirely clear so not sure.

 

There does appear to be some sort of fungus infection by its left fin. But I do see the scratches he's talking about, located directly between the fish's eye and gills. These scratches are most easily visible in the fourth picture.