Lone cory

[beatle]

6 months ago I bought a tank that had an angel, a full grown emerald cory, a silver dollar, and a pleco. I've since given the silver dollar and pleco away, but I have the cory and angel still. Since cories like to school, I bought two spotted and two pandas, all about the same size. They all get along great and often form a shoal. The emerald rarely swims with the others. Is this because he grew up alone and that's all he knows, or is it that he is different enough from the others that he doesn't fit in? Another reason?

[robinos]

from what I've read corys tend to stay with their own kind. Albinos with albinos. Pandas w/ pandas. Even when kept with their close "cousins." He'd probably get along better with his own type. But I imagine it's still a step up from being alone.
-Robin