Can fish be afraid of light?

[Praetorian27]

My daughter's 10 gallon tank has one goldfish in it, and he is an active healthy fish...as long as the light is off. If I turn on the 15 watt light, he freaks out, and hides inside a cave all day. When it is off, but the room light is on, he acts normally. Needless to say, it doesn't lead to a pleasurable looking tank! Could this just be too much light for his eyes? Or is he just jumpy?

 

[Newman]

he's in a 10 gal tank, thats you main problem lol.
but to answer the question, yes fish sometimes can be afraid of bright light.
what you should do is throw a lot of floating plants (plastic/silk/live hornwort) on the surface to shade from the light, and the goldfish should be better. also provide more hiding spots like that cave. get another cave, or make one out of rockk....
just some suggestions aside from getting a much bigger tank.

 

[rugrat]

I had a tank full of fish that would crowd together and shimmy whenever you turned the light on. When you turned it off they'd act totally normal. Even with a plan incandescent bulb they did this. I added tons of decorations and a cave and they were a lot better after that.

 

[Jwoody]

i have a few fish that are like that too, but mine only hide when i first turn the light on. they calm down after a while

 

[abigor0329]

Unlike nature when light slowly shines, aquarium lights pop on suddenly and do scare some fish. Hence why they make moonlight lamps. But anyway, maybe switch over to a fluorescent light instead of an incandescent if it is that kind. They are much better looking and cooler tinted light.

 

[anshuman]

All fish react to strong light , the killifish i have go in instant Ninja mode and hide in the tank, check the video in the sig , there are 14 killifish there, you be able to spot only some of them. I am keeping a floating riccia island , which seems to calm them down rather than startle . but they still go nervous when i move close to tank.

so strong lights can make fish nervous. better off with some plastic plants (soft) and some floating plants as suggested about.