Bangaii Cardinal Question

[N1Husker]

I bought four Bangaii Cardinals at Barrier Reefs big sale a few weeks ago. I quarantined for two weeks and put them in the tank.I lost one intially, he was very small. My question is that the other three, I thought would kinda hang together in a school, but one is in one back corner of the tank, the other is clear on the other side of the tank in the back corner and the third will either hang by himself in the back of the tank or down in the back corner with one or the other. Is this normal?

 

[Herefishyfishy]

There is no normal in how the juvis congregate, and can be very competitive and aggressive to their own.
The smaller ones will be chased away by the larger whereas groups of similar sized ones tend to school.

How big were they across the fins in comparison to a coin?

 

[N1Husker]

Mike, They are from tip to each tip of the fins about the size of a fifty cent piece and the body is about the size of a nickel, all of them about the same size.