Lamp PL 11W TriphosphorThe Aqua One Light Bulb PL 11w Tropical. These tubes produce a mix of lights; Sunlight and Tropical. One light produced is a natural brilliant white light similar to that produced by the sun. Sunlight provides the basic life cycle requirements of many aquatic animals and plants, whilst enhancing the natural beauty of your aquarium. The other is a light specifically designed to provide the light that plants need to photosynthesise. Converting carbon dioxide to oxygen within aquarium water is one of the key benefits of keeping live aquatic plants and a healthy aquarium.