For many years, the tiny blue 1watt LED has been a staple in aquarium lighting fixtures. Used heavily in older power compact and T5HO lighting systems, the blue LED served as a faint source of light for nighttime aquarium viewing and added some perceived lunar simulation. With the prevalence of the moonlight in aquarium fixtures, many believed there was some significant benefit and that somehow aquarists were recreating natural conditions that there fish and corals simply could deal without. But are those lights really that important?
Anecdotally, we will say yes and no, with us leaning more toward the no. A full blown reef tank can operate just fine without the use of a moonlight. That said, there has been some situations where moonlighting has helped certain fish or corals spawn, or at least that has been the perception. There are too many triggers that initiate the breeding sequence, but that’s a different story altogether.
Whether or not moonlights are important functionally, there is little doubt as to their aesthetic benefits. The reef tank comes alive at night, and there’s no better way to view it than with a moonlight. Just don’t go overboard with the light and give your tank a neon blue look. All you need is some faint lighting, preferably white LEDs, to get the best look.