They do hang together but bicker and nip each other constantly at this size. As they've grown Ive noticed that they are very similar to piranha when in a pack. They even pick fights with my larger Armatus and he puts them down quick, just rams into their side with his mouth. Interesting though as they don't really bite each other, considering the size of their teeth it would be fatal arguments. Usually just a single ram once challenged and then the loser will move to the back of the pack. The Armatus seems to be outcast as they usually wont pack with him and he keeps to his own area, but on occasion they will all shoal together in one big formation with my ATF's and Tarpon. Very neat fish and easily as impressing as the lone wolf Army when together. Depends on location and importing as here in Canada Ive seen juvies of all types. Armatus being extremely rare and expensive up here.
