Grow Out Behaviour

I have my first batch of fish into grow out.
 
There are three species all in the same grow out tank.
 
The wierd thing, is that the majority of each species has taken up residence in a single corner per species, in a tight group.  These groups are exclusively single species.
 
There are a few (10-15%) that have not joined in this behaviour and explore the tank, but them come together as a mixed group in the last remaining corner and dont join their species group.
 
Have other people seen the same thing or do I have wierd fish?

Which species do you have together? Also, are they all around the same age/size? I've seen similar behavior so, no, you don't have weird fish, lol.

http://www.fishtalpropagations.com/#!home/mainPage
"Making captive breeding easier."

Amphiprion ocellaris, Amphiprion clarkii, Amphiprion frenatus
 
They are all about the same size (clarkii are slightly more stocky), ocellaris are smallest but most numerious.
They all hatched within about 2 days of each other.