I'm sorry you had to euthanize your angel, it's always a hard thing to do.
I didn't see your pics when I answered you. That pink area by it's eye doesn't look good. It could have been a wound or a sign of disease.
The orange color is normal in some angel strains.
Distilled water is not a great idea, fish need some minerals in their water. Do you add anything to it to help with that?
I add start right to the water. Is there better water besides aqua water. It was recommended by the pet store when they were out. And then the weekly water maintenance stuff nitrate/nitrite...