Light Too Bright

[lopeva]

Whenever I turn on the aquarium light, my tetras seem to freeze. As soon as I shut off the light, they begin swimming normally. Any suggestions on a different bulb I might try? I don't want to stress the fellas out.

Penny

 

[jesssa]

Mine do that too. When the light is off they are playing around chasing each other and swimming happily, but when the light goes on they shake with fear and retreat to the corner together all five of them really close. And my lone khuli freaks like it's been shot. I bought a floating plastic plant thing that sort of covers them from the light and they like that but they still get scared when the light somes on. So I'd also like to hear people's light suggestions!

 

[Lateral Line]

Fish do not have eye lids, they can't close their eyes. Instinctively, if the light level suddenly changes, then they will react - most fish, not just tetras will do the same.

The fish don't really appreciate the difference between the tank and the wild - their instincts and reflexes are built for the wild situation.

If the light suddenly gets brighter, it may mean whatever was sheltering/shading them from the light has suddenly moved - may be a heron or other enemy. Same thing if it suddenly gets dark, an animal has come over the top of the tank and is going to eat them. Whichever, the "I'd better get out of here fast" behaviour kicks in.

It is called the "fight or flight" reflex. Most animals have it. If something "makes you jump" you have experienced it.

 

[lopeva]

Lateral Line...

Thanks for the input. I guess I never thought of the flight or fight impulse they might feel. So it's very possible the light change is stressing them out. I'll have to try to lessen the light so not to upset them too much.

Thanks again.

Penny

 

[clutterydrawer]

you could try adding some plants, especially floating ones, to give them extra shade.

 

[swampcat]

I put a strip of duct tape on hood glass top to partialy block some of the light, works well.

 

[~FairyAngelFish~]

Hmm. Does the light also heat the water a bit? I know my water is a bit cooler than what it should be at. Because I leave my light on at night when I'm not in the room for like an hour or two and all the lights are off because i read somewhere that they need bright light. and i dont want them to get blind. lol

 

[Teelie]

Lighting will warm the water up if it's got enough wattage. I have floating plants in 2 of my tanks and lots of hiding places and tall plants in the others to help break up the light for the fish.

 

[Lateral Line]

>>> that they need bright light.

Fish don't need lights on the tank at all. Daylight is quite sufficient.

>>> light also heat the water a bit

Fluorescent lamps run pretty cool. The ballasts, particulaly the older types can get quite hot, but they shouldn't be inside the hood anyway. Regular incandescent and Halides lamps get very hot and can heat the tank quite dramatically - can be a problem for people living in hot countries, (so not a problem for me!).