Pink Smith Damselfish spawning behavior??

[Acros]

I have pair of Pink Smith Damselfish in my tank since 7/11/21. They were roughly the same size. However, one has gotten significantly larger and develop more blue on its head. They were out swimming until this past Monday. The bigger one is now spending 95% of the time guarding something/hiding next to a rock.

Whenever it comes out to pick off some copepods, its skids back (almost panicked) very quickly to the spot. There is no aggression between the fish. They are the only fish in the tank. I do not see any signs of disease either. Is this breeding behavior? Is the fish guarding eggs?

This is where it spends all its time.

 

[Timfish]

They're sequential protandrous hemaphrodites like clownfish so you most likely have a pair. it seems too soon for them to be breeding but you could be seeing the social behavior that determines who is the female and who is the male.

 

[Acros]

The bigger one is always in that spot. The smaller one swims around like normal. The smaller one gets chased away half of the times it gets near to the protected spot.