Red light at night

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DmitryB

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So I understand that fish don't see red light? And if you shine it on the tank at night, it won't wake them up. Does that include the red lights in our lighting? Radions, for example, have a separate Red spectrum. F inactivate just that at night, it really won't bother them? Is this true for all fish? Does this also apply to shrimp?
 
Most fish do see red light. I had a pufferfish that would try to jump out of the tank if you wore a red shirt.

I got splashed by sturgeon way more often when I wore red or orange.
 
I have three switches on my Apex breakout box for my Radions, 100% white, 100% blue, 100% red. I sometimes use the reds at night to look around. Most of the fish ignore it, but my powder blue and monoargentis Angel both seem to see it. But these two also can’t sleep if I turn on moonlight. Most inverts seem not to notice.
 
Losing the ability to see red light tends to be more of a deep-water fish thing. Red is the first color to "attenuate" from the spectrum as it passes through a medium. That's why the ocean and the sky look blue. It's also why you need more red light for plants as opposed to corals, especially those in deep water. Things that live deep don't experience it much.

Red light in general is easier on our eyes. I'm not sure whether the same extends to fish, but they were the ones to evolve the eye as we know it!
 
Losing the ability to see red light tends to be more of a deep-water fish thing. Red is the first color to "attenuate" from the spectrum as it passes through a medium. That's why the ocean and the sky look blue. It's also why you need more red light for plants as opposed to corals, especially those in deep water. Things that live deep don't experience it much.

Red light in general is easier on our eyes. I'm not sure whether the same extends to fish, but they were the ones to evolve the eye as we know it!
That would make sense why the Mono and the Powder blue see it.
 

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