Aqua One Lamp PL18W Sunlight recreates the natural light spectrum of the Sun. These Lamps emit a refreshing natural white light. Sunlight Lamps brighten the world inside aquariums and terrariums, plants thrive, fish look better where their colours appear more vivid and attractive in a natural way. For a marine aquarium to realistically represent reef life, it is essential to provide the best conditions for corals and invertebrates to thrive. Most important in this is the survival of zooxanthellae, a specific form of algae, which symbiotically assists the invertebrates to feed and remove waste matter.