With more and more people converting their aquariums to LED driven systems, it is important to keep in mind that corals may not be able to instantly adjust to the new lights. As our metal halides and fluorescent lights age, their intensities degrade slowly. Corals adapt to this new, lower intensity, and any time you put a new light over the tank, they can suffer from light shock. Because of this, hobbyists should always slowly acclimate their corals to the higher intensity lighting, either by slowly increasing the intensity or the duration (or both). Luckily, many LED fixtures have coral acclimation programs, and if they don’t have that specific setting, there are plenty more of easily adjustable settings that can make the adjustment easier.