I have 6 corys that are supposed to be shoaling fish - I don't think I've ever seen all of them together They all go off in different directions doing their own thing Same with my neons, zebra danios and platties Go figure
If youre looking for a group of shoaling fish, why not consider some Rummy Nose Tetra and get about 10/15 and they will spend all the time follwing each other.
Make sure when you buy them that the faces are bright red , this shows good healthy fish.