Cory Being Singled Out

[JArnold]

hi i have very recently purchased 3 panda cory all from the same place but one was bought first then about 3 days later anova 2 were bought however 2 cories are pretty much sticking 2gever now and the other is being singled out, is this normal? will the group together? should i buy another panda in few days so one can't b singled out? lol i dont no

thanks for any help