Random aquarium/fish facts

[Deadeye]

Baby piranhas look like tetras so they can blend into the school and eat as they grow.
Red wolves do the same with a certain type of killifish.

 

[MultipleTankSyndrome]

-Because of their super-long barbels, pictus catfish have the 'personal space' needs of fish twice their length. So they should be kept in tanks at least 12x their length and 3x their width as opposed to the usual 6x the length and 1.5x the width (for the spotted pictus, that's a minimum of 473 liters).

Somewhat similar: gold zebra catfish probably shouldn't be kept in aquariums any less than 18x their length and 4.5x their width. Not only do they have the same long barbels as pictus catfish, their tail extensions are comparable in length to the rest of the fish.
So that would mean minimum 10.8 meters x 2.7 meters tank size (at least IMO).