SUN-GLO Fluorescent Bulbs by Hagen

General purpose aquarium lighting for freshwater aquariums. Offers refreshing, natural white light and simulates full daylight with full sun spectrum and standard intensity. Made in USA. How much light does your aquarium require? Appropriate lighting for your aquarium is essential to create and maintain a healthy aquatic environment. Many factors influence the type and quantity of light required: Size of aquarium Fish species and other inhabitants Plant life Filter media Aesthetics To achieve appropriate lighting, a general rule is to have a range of 1 to 3 watts of light per gallon of water in your aquarium, subtracting 10-15% of the tank volume to account for volume of materials inside the tank. Adequate lighting range = (1 to 3 watts/gallon) - (10%-15% of tank volume)