On Vision and Colors tried to demonstrate physiologically that color is "specially modified activity of the retina." The initial basis for Schopenhauer's color theory comes from Goethe's chapter on physiological colors, which discusses three principal pairs of contrasting colors: red/green, orange/blue, and yellow/violet. This is in contrast to the customary emphasis on Newton's seven colors of the Newtonian spectrum. In accordance with Aristotle, Schopenhauer considered that colors arise by the mixture of shadowy, cloudy darkness with light. With white and black at each extreme of the scale, colors are arranged in a series according to the mathematical ratio between the proportions of light and
Full-spectrum light tropical and marine fish as well as many other water pets. The use of full spectrum lighting assists aquarium plants to grow and aids in the health of the fish and the tank as a whole. While plants have adapted to the reception of real sunlight, full spectrum light bulbs often mimic the emphasis of wavelengths of sunlight enough that plants are stimulated to grow. Full spectrum lighting also enhances the natural coloration of fish, plants and other aquatic elements in an aquarium, which are often discolored by artificial lights. Full spectrum lighting is typically used more in fresh-water aquariums