It was said that fish can't see the red spectrum of light

[cjburden]

and that as such, red would make the ideal choice for a 'night light'. However I wanted to say that the fish in my tank seem very reactionary to the red LED moonlight that I made. As soon as I turn it on they become more active and if they were sleeping, soon are not. My question is where did this statement that they can't see red light come from, and is there in fact any truth to it?

 

[fshhub]

not too sure about that statement, butI can say that
We use a red lens cover to view our tanks at night(we being many of us here) because a red light does not project a beam aand thus does not spook the critters that only come out at night(nearly as fast)

 

[coralcollector]

they prpbably wouldnt see it in a real deep tank but in shallow water they can see it.