[Delphinus]

Good catch, I forgot to mention about the dusk/dawn effect. A very good thing indeed. But again of course you don't "need" actinics for it ... you, may, however "want" actinics for it (and for very good reasons). Colours do come out more with actinics and of course a dusk and dawn with fluorescing corals is indeed very nifty to see (I myself wouldn't be without it either [img]smile.gif[/img] ). Supplementing with something (be it actinics or otherwise) is still a good idea because if your tank is at risk for overheatings on a hot day, you can switch off your halides and still have some leftover light from the supplementation -- which means to the tank inhabitants that it is "cloudy" as opposed to "nighttime when it should be daytime." I have no idea how important this may be, perhaps not, but I think it is nicer to the tank inhabitants to not be messing about with their photoperiods in a sudden or drastic measure. So anyways if you're going to have some supplementation ANYways then why not have at least some actinics. Just my $0.02..