Black rays on sanke’s pec fins call tejima
And Showa call “motoguro” we always joke that a buff guy with tattoo on his arms looks better
Compare again with a Showa and you can see they totally different types of black or sumi
Go into this thread and you can see the different in big/small tailtube from my 2 koi
https://www.koiphen.com/forums/showth...e+illustration
It’s kinda hard to tell when they are little but try to pick the thicker tailtube section before the tail start
Stronger tail bone swim faster and to the food
Good luck