Why Do My Fry Fight

[zuulan]

I have 9 Swordtail fry born on the 27th December and they always seem to be fighting & having a go at each other. Is this normal?

They are in a 50ltr new but cycled tank which is shared only with 3 Apple snails. They are perfectly healthy with large bellies. I feed them 3 times a day and everything else seems fine.

 

[OldMan47]

I have seldom seen any aggression in fish that young Zuulan. Adult or near adult swordtail males sometimes spend a great deal of energy establishing dominance, but it would be quite unusual for 1 week fry to do that.