it's certainly entertaining, but is it mean to the fish???

[Magnum Man]

I'm watching my 2 yellow tail male African Tetras (Alestopetersius caudalis) in a "display battle", and while it's entertaining, and no fins are shredded with this species, their dander sure gets flaired up... most schooling fish avoid the body damage, but the exact same thing, in some species, could result in a battle to the death... in the wild, would these tetras separate, so the males are farther apart, and display for the females, or do the males get in each others faces, in the wild, like they do in the limited space of an aquarium??? these two seem to always be next to each other, often with no females near... a prime example, is in the picture of my tank of the month submission for this month...

 

[Magnum Man]

the smaller younger one ( above in this photo ) is much more colorful, with more extended dorsal

 

[gwand]

That is interesting. I have 6 Alestopetersius caudalis in a 4 foot tank. They never squabble among themselves. But this tank has issues. Four of the six Anomalochromis thomasi (2 pairs) have fry at the moment. One pair has declared territory of the left two feet of the tank. The other pair has claimed the right two feet of the tank. The poor Alestopetersius caudalis are being confined to the center two feet of the tank along with the remaining Anomalochromis thomasi without fry. It’s like there in prison. Much havoc in the tank until the fry become juveniles.

 

[MaloK]

In nature they would establish larger territories, still would patrol regularly and repel any intruder invading. The proximity of territories intensify competition between males. In nature the "dominated" flees promptly or accept the pecking order imposed by the strongest.

The absence of females, shifts the focus from courtship to dominance displays between them.

 

[GaryE]

I didn't get to watch tetras in Gabon, but I did see colourful large barbs having dance offs. Cichlids too.

They were living in connected groups - keeping an eye on each other but a few feet apart most of the time, and constantly moving in an area about the size of an average house. They'd flare and spar quite regularly, as they met up with each other all the time. I just stood there in water to my knees knowing they were too fast to catch in open water, and that the barbs were too big anyway. It was the best TV show I've seen.

The Cichlids there were mouthbrooders, so they had a different sense of territory. The barbs were just busy, as barbs tend to be,

In tanks, that can become a fight to the death, because the behaviour gets twisted by the glass walls. Normally, they meet, flex, maybe have an intense dance off. The loser goes to McDonalds while the victor stays on the dance floor and tries to impress the next fish along. They seem to do that all day long.

 

[CassCats]

These behaviors raise valid questions when it comes to tank sizes. While what we recommend in captivity will never replicate true nature, it's does prove over and over again that providing as much horizontal space as possible allows more space and cover options for these such situations.