My blood parrots are pretty smart, but my large one is the smartest. We've owned him the longest. He loves to know whats going on outside the tank and even when we are in a completely different room, he seems to be able to know where we are and watches us through whatever side of the tank we are on from 2 rooms away through the doorways.
He also likes to swim loop-de-loops through his caves whenever we come by to show off how cool he is, not to mention being the boss of the fish tank. He's a funny and personable fish.
My Demsey is a ball of personality but i sometimes doubt his intelligence. Id have to say my parathraps fenestratus or camaco pink or whatever they are labeled as now. He is alert and well aware of his suroundings at all points. Plus he sleeps where the crayfish wont get him haha
My Red Bellied Pacu. He recognizes the food cans when I bring new ones home. and acts differently depending on whos walking through the room. He also has a fear of nets, I cant even get them out or he hides.
My Fahaka puffer is WAY smarter than any fish i have ever owned. It is down right scary the thinking and problem solving ability that he has. I watched him one night use a branch from my manzanite tree to help pry open a mussel, craziest thing I have ever seen. Oh, he laso watched t.v. like it is going out of style lol.