Fish behavior question - fin flaring w/ no aggression

[saltybagel]

Hi guys, I have a quick fish behavior question:

I have 2 clownfish, 1 possum wrasse, and a hectors goby in a 40g tank. Occasionally when I'm observing them, sometimes one of the fish will swim and float next to one of the other fish and flare their fins out (and the other fish will do the same back). It's almost like they are sizing each other up, and then they will meander away from eachother and continue whatever they were doing. This is not isolated to one fish instigating this, I've seen this behavior mostly started by the clowns, but also observed it with the possum wrasse and the hectors goby.... which I was able to capture in a somewhat blurry picture below:

All fish are eating and acting normally otherwise. No torn fins, charging, nipping, other fighting or stressed behavior to note. They for the most part all sleep together as well and seems to be a very peaceful community.

Thoughts?
Seems like territory/dominance type behavior, but I'm no expert and would love some information on this. If anyone can point me to an article related to this, please let me know! I would love to read up.

 

[cdemoss01]

Hi guys, I have a quick fish behavior question:

I have 2 clownfish, 1 possum wrasse, and a hectors goby in a 40g tank. Occasionally when I'm observing them, sometimes one of the fish will swim and float next to one of the other fish and flare their fins out (and the other fish will do the same back). It's almost like they are sizing each other up, and then they will meander away from eachother and continue whatever they were doing. This is not isolated to one fish instigating this, I've seen this behavior mostly started by the clowns, but also observed it with the possum wrasse and the hectors goby.... which I was able to capture in a somewhat blurry picture below:

All fish are eating and acting normally otherwise. No torn fins, charging, nipping, other fighting or stressed behavior to note. They for the most part all sleep together as well and seems to be a very peaceful community.

Thoughts?
Seems like territory/dominance type behavior, but I'm no expert and would love some information on this. If anyone can point me to an article related to this, please let me know! I would love to read up.

Probably warning each other that this is my territory etc. Wouldn't worry to much if they aren't attacking each other. Cool though!