I posted this before on one board the consensus was actenic are simple to make the reef look blue. (just for show).
The other board said it was necessary for coral, they somehow utilize the color.
What do you think, any proof?
thier not necissary at all. their just there so it looks more pleasing to the eye. the only exception i can think of is if you were using say a 4000k spectrum MH then an attinic might be necissary to get the full color spectrum.
If its just for show we are paying a great deal of money just for a blue light. Even changing them every six month so we don't get too much of a spectrum shift.