I just witnessed my first loach fight.

Err...apparently they weren't done yet. The largest and smallest of my Histrionica are still squabbling. They don't appear to be doing any damage, so I'm not too worried. I am a bit surprised though. I had expected to see this once they were a bit bigger, but they are barely 2 inches!
Looks like they are done now. The small one is the most aggressive of the bunch, but it looks like he lost. He's still faded, but the other one is bright again.
Are dominance fights common among a group of young loaches like this?