Last point.
People don't think fish aren't intelligent. They are. I have trained fish to jump out of my tank. They follow my hand. I have yet to have them let me stroke their sides (gotten close). Some Oscars, trained correctly, will shove a ping pong ball threw hoops and put them in goals. I don't have time to try that.
This was interesting. The laser pointers that you play with cats/dogs. I was playing with the cats and thought, what the heck, and pointed it into the tank. Dang the upside down cats, the danio, the sliver dollars, the dempesys, the parrot nose cichlids were all chase the laser pointer
Plecos didn't give a crap
Not as much as a cat or dog crazy, but were stimulated by it. Funny.