Betta and tank lighting

[P_W]

I have a male betta in a 2.5g tank, and everytime I turn the aquarium light on he starts puffing and flaring his gills. I'm pretty sure he's seeing himself since the light is coming from the inside of the tank. Does anybody else have this problem? Atleast without the light on I've had no problem with algae.

 

[kelliope]

I've had bettas that do that also. He will get over that if you were to leave it on. Bettas do like somewhat subdued lighting. Do you have live plants?

 

[InR reason]

PW it's not so much a "problem" as it is your fish's natural instinct. If they see a reflection of themselves with the light then they will flare and go into a little frenzy ready to fight. All of my bettas do this at one time or another and it is perfectly normal and healthy.

 

[TheZoo]

Try some floating plants to break up the line of sight a bit. It'll also give him something to play with/around. But, its not a problem for the fish unless he does it constantly, I suppose then it could stress him out too much.

 

[Ms.Bubbles]

If the ambient light in the room is brighter than the tank lights, your betta will not be able to see his reflection. If you can, try opening your curtains wide, etc. to raise the light level in the room.

My betta flares like this in the winter time when daylight is low and days are shorter, but it's never a problem in the summer when light levels increase.