Wanted to show off my Threadfin males sparring off
These guys are pretty rare in the hobby! Threadfin rainbowfish or Iriatherina werneri.
The males will square off like this to establish dominance. The presence of females increases their sparring/brightness of display colors, but mine do it even without.
I hope I’ll be able to find some females someday and may potentially try breeding them simply so others can enjoy this underrated nano rainbowfish.