Originally Posted by Sushi
Whenever my betta, sushi, seems bored i hold up a mirror and he flares. He gets really excited and swims all tough, like showing 'better wachout this is my tank! Dont mess with me!'. I was only wondering how often i should show him his reflection and if it is stressful to do so too often.
It is just a territorial thing. Male bettas do not like other bettas, so it is natural they "flare."
You should put a mirror near his tank every once in a while; I read somewhere that it gives the bettas some exercise. Don't do it for a long time though.