Replacement bulb for Aquatic Life's HID light fixtures. HID - High Intensity Discharge bulbs produce a greater amount of light output per watt of electricity input making them a very energy efficient high output lighting choice for the energy conscious hobbyist. The 6000K bulb will produce an intense natural white lighting effect that resembles sunlight. Ideal for live plants and refugiums. Balanced light includes peaks in the blue and red spectrums that closely matches the chlorophyll absorption peaks in plants and enhances fish colors. HID bulbs should be replaced every 9-18 months depending on the application they are being used for.