Odd problem

[sl60]

Th is is just a speculation, but I wonder if you could take the original photo (as a png) and copy and paste it into a new document of thesolid correct color you want. Then this color would show through the tail in the more transparent parts. Then select the area around the fish and make it transparent and save the whole as an png. best to size up the photo to at least 3X so you can better see what's going on.