The fact that he is getting the pimples is not bad, but I would be concerned with the toby picking on him. He will eventually stand his ground, but only when he grows substantially in size. If he is still small now, I would say that one of the fish haf to go (unless you can move him into a less aggressive tank for now until he grows). I had the same situation with my puffer and an aggressive grouper that thought it was his tank.