well he died. i dont know what happened. His face got really red and he had some blood streaks under his mouth not gills. Did he hemorrhage for some reason?
Could it have been septicemia? Red streaks can be a sign of that.
Did the streaks look like raw abraded or scratched skin where blood might have been oozing to the surface, or as in red streaks that show near the surface of the skin but under the skin?
Were the streaks thin well defined lines, or more diffuse?