Are there light colors that stress fish

[gwand]

My aquarium lights can be cycled to produce red, blue, green as well as white light. Will any particular color light be stressful to fish?

 

[Magnum Man]

I think that a lot of it also depends on intensity…
Red light is supposed to Enhance some algae growth, and originally I did less intense red lights for sun rise and sun sets, but about 6 months ago, I switched to blue lights, fading into white, for sun rise, and sun sets… I personally think any of those colors, in a less intense setting, won’t be more stressful, than the next

 

[GaryE]

I've never heard of any problems. Back in the seventies, red, green and blue incandescent bulbs were the way to go, as they reflected well off my plastic galleon wreck.

 

[Colin_T]

Do not use one particular colour for long periods on its own unless its white. Other colours on their own (blue, red, yellow or green) are not natural and will stress fish. In the morning you can have low levels of yellow on for 30 minutes before adding red and other colours but don't leave yellow (or any other colour except white) on all day by itself.

Most fish (and all freshwater fishes) want normal coloured light just like people. Fish have better colour vision than people too.

Normal daylight starts with yellow for the first 30 minutes. Then some red, then some green and blue. By the middle of the day the blue and UV are at their strongest and the intensity is also at its strongest. In the evening the colours fade out in with UV and blue going first, then green, then red, then yellow at sunset.

If you have a programmable light unit with different coloured LEDs, you can either run it like natural sunlight, or just have all colours even and have the light start with a low intensity and increase to full intensity over an hour or two in the morning, then reverse that in the evening.