Black Tetras Bullying

[BethK]

I have 5 black tetras, that all came from the same tank at the LFS. I have had them for 3 weeks but this morning, 4 of them keep chasing 1 of them. Not all the time but I have noticed that they have been chasing this 1 tetra over 10 times this morning. One nips at it but I can't see any damage on any of the tetras.

They are currently getting along but just a little worried they will damage this 1 tetra.

 

[BethK]

Update

After watching my tetras for a while, it seems 3 of them are culprits, one sits away from the group on a regular basis, seems to be watching all the time. They seem to be playing chase but it's always 3 chasing 1, I know it's the same one as she/he is smaller than the other 3, not by much but the red crescent over the top of her/his eyes is not as bright red as the other 3.


Are they bullying? Or is the one being chased a female and the others male?