Why is light necessary?
Light is essential for growing aquatic plants not only in Nature Aquarium but in any aquarium. Green plants, which include aquatic plants, capture light on their leaf surfaces and perform photosynthesis.
Photosynthesis is a mechanism with which plants synthesizes glucose from CO2 and water using light energy. Oxygen is produced as its byproduct. Photosynthesis is not only essential for the healthy growth of aquatic plants but it also supplies oxygen to fish and microorganisms.
Lighting in an aquarium has the same role as the sun in natural ecosystems. Natural sunlight is hard to utilize in an aquarium depending on the place of installation or due to the fact that the intensity and duration of sunlight cannot be controlled easily. If strong, direct sunlight shines into an aquarium, algae may grow on aquatic plants. Phytoplankton also tends to proliferate and this results in green water. Therefore, artificial lighting becomes necessary. However, it does not mean that just any light will do.
Besides providing light to aquatic plants for photosynthesis, lighting has another purpose of illuminating an aquarium beautifully for viewing as well. The colors of aquatic plants and fish do not appear beautiful with a red grow light designed for terrestrial plants or lights intended for indoor lighting. An aquarium requires the light that makes a layout appear beautiful and still promotes photosynthesis.