Those fish all look like skinny, young, freshly, imported VATF to me. I don't see anything particularly unusual about them. Get them on a quality diet, put them over a dark substrate and put a black backing on that tank and they'll be stunners in a month.
Then, a few months after that, they'll have killed each other and you'll only have one. Sell the ones you don't want now and get your money back.
ATF stop schooling by the time they're about 2" long. Those feeding vids that we all see on Nat Geo and the like with the huge schools of ATF are feeding frenzies of vittatus in the Okavango during the annual flood, which triggers spawing for many species of fish, which get the catfish concentrated, who then in turn get eaten by the schools of VATF. That isn't normal behavior.