Ms.Bubbles said:I don't think I'm going to show my betta a mirror any more. After moving mine into a slightly bigger tank, I thought I'd amuse him with his reflection. He got VERY VERY excited, started darting & flaring & became a very "angry" fish after that. He built massive bubblenests all day & night & acted aggressively toward the side of the tank that he saw the mirror. At other times he would stare for hours at that side of the tank, virtually ignoring people altogether. Next thing I knew, he was lethargic & sickly for a few days, barely moving. He's recovered now (took about 2 weeks) but I don't wish to put him (or me) through that again! I might try the ping-pong ball thing though, sounds fun.
Mine totally ignores the mirror ... after making sure it's not a brightly colored bloodworm or other food item