I've got five of them in quarantine right now. They were two bucks apiece when I bought them. They're seasonally available, and currently in season. There are about 50 species of characidium, so maybe behaviour varies, but mine definitely don't school. There is some aggression, however. It's nothing too serious, but I'm keeping the lights dim for most of the day to reduce the amount of time they spend jostling each other.
The trickiest thing was getting them to take non live food. The only thing they'll eat right now is frozen bloodworms, and it took a week to get them to accept even those. They'll eat flakes if they're excited enough, but then spit them right out.
The trickiest thing was getting them to take non live food. The only thing they'll eat right now is frozen bloodworms, and it took a week to get them to accept even those. They'll eat flakes if they're excited enough, but then spit them right out.