Odd Black Tetra

[deanoce]

Hi all, i have noticed on one of my black tetras a strange vertical band near the tail fin of one of my black tetras today, it looks really strange an i have no idea what it is or if its ill,
If anybody knows or thinks they could help me identify it i would be really grateful.
Thanks, deanoce
(ps. i will try and get pictures soon)

 

[Noahs ark6]

Most likely just a deformity. If so its not treatable. happy fish keeping.