Changing the bulb in your aquarium is vital to the growth of your plants and corals. The blue spectrum will fade and cause health problems to the corals. It is recommended that you replace the bulb in your tank every 6 months to maintain healthy corals and plants.
10K/Actinic Blue Linear (straight) pin configuration. B9-BW10K
One side of the bulb is actinic which is a very deep blue, great for growing corals.