I started off with something like 14 neon tetras but they were all eaten execept one and now Ive had that one for about 6 months and decided that I was to get more tetras again as the fish that ate them died. I got 5 more now but they dont stay together as a school and dont look as good. Also the one I had for 6 months is always hanging aroung the back and he's far bigger than the rest. I want them to school ! All they do is fight with eachother-what to do???