One of my sens at least, maybe 2, has a reddish area around the tail fin. I wouldn't describe it as streaks but maybe it's similar. I always assumed it was just where they thinned out and let more light through their skin.
nah.....im almost almost sure the gar grabbed it....my buddy has a small senegal with a florida gar too.......one day i noticed the redish marks on the senegals tail 2......later that day i noticed the gar had the senegal by the tail but got away and it seemed fine afterwards.... normal, not even traumatized and still swimming around the gars face......within couple days the senegal turned into gar $h1t.... is ur senegal small enough for the gar to eat?