this was cute until i realized the fish is probably trying to not get eaten
A fish trying not to get eaten wouldn’t slow down when the “predator” slows down. It also wouldn’t constantly swim in a circle near the edge of the tank; It’d try hiding. Also a fish in a tank in a a public place that is constantly filled with people is not likely to see people as predators.
Animals, I think people tend to forget, also enjoy playing.
Small reef fish like this evolved for an ecosystem where hundreds, even thousands of different animal species live in extremely close quarters 24/7 and the majority of them are bright and colorful, rather than living camouflaged and hidden like life in a forest or desert. To survive in such an environment it is a necessity that they have extremely adaptable brains capable of categorizing what’s dangerous, what’s useful and what’s of no concern. I can guarantee it does not consider humans predators, and knows humans are the things that bring food! With a mind that sharp and inquisitive it is probably copying what it sees just in case that’s an important thing to do…or it really is just getting satisfaction from the activity.
