Tip of the Day – 1/6/2012

It has long been believed that aquarium lighting on the bluer end of the spectrum emits less PAR than lights that are more yellow or white. This has led many people to stick to the notion that white bulbs are better for growth while blue bulbs are better for coloration. Despite firm seated beliefs based on anecdotal evidence, these two ideas may not be entirely accurate. It is a not so well known fact that certain PAR meters actually under read various portions of the visible light spectrum, most notably the blue end. This would cause blue lights to register a lower reading on a PAR meter and convince aquarium keepers that blue lights are not at good for coral growth. On the flip side, white lighting isn’t exactly bad for coral coloration. Sure, corals glow under heavy actinic lighting, but in nature, corals are constantly bathing in the yellow rays of the sun and seem to be just as colorful, if not more colorful, when compared to their captive counterparts. This could be due to the fact that most wild corals live in fairly pristine water conditions where nitrate concentrations are low enough that it doesn’t cause the corals to brown out.