apparantly fully 100% impossible to tell until they pair up and breed. even then people guess which one is what, until one actually lays eggs.
my bigger one seems to have a bigger hill like thing (as if it were a females vent) and the smaller is uch flatter down there, with a sharper and more defined thorn like appendage. plus the smaller is more bossy, brave and dark, but they can all be female things too :S
i just hope they arent both males!!
hows the fish? none bullied or anything? xx