Cory behavior

[Phoenixphire55]

I have four bronze cories in my 15 gallon non-aggressive tank, and the smallest one always seems to be off by himself while the three bigger ones are always in a group. The little one goes to the group at feeding time or when he feels threatened I think. Just curious if anyone else has noticed interesting social behavior in their cories.

 

[Zagz]

Schooling fish like cories do have a hierarchy. You are right when they feel threatened or frightened they stick together like glue. When happy and content they are more likely to spread out.