Fish "dance" Against Each Other = "fight" For Dominanc

[Ram8349]

I filmed this a while ago.
From time to time, my Black Phantom Tetra would do that kind of "dance" @ 0:36

As well as my Harlequin Rasbora did @ 1:30 into the video.



I know for a fact I have only 1 male Black Phantom and 7 female. The females are "dancing" against each other too, so that should mean it's not mating dance. I can't tell the sex of Harlequin Rasbora though.

I never really figured it out what they were doing.
Simply playing or try to see who is the boss?

 

[bae1994]

I'd say showing dominance (showing who is boss)

 

[Ram8349]

I forgot to mention.

Once in a while, when the Black Phantom Tetra do this kind of "dance" against each other, a few of them would "cheat". That is, when they do the dance, they all extend their fin to the fullest. The 'cheaters' would suddenly bite on the other fish's fin. That does not happen most of the time, but when it happens the victim would have a damaged fin...although it grows back in 2 days like new.

 

[bae1994]

It sounds like dominance if you've got room I'd add a few to the shoals then it should spread the aggression out