Do you have stubborn algae in your pond, or has your bulb just gone bad? Danner Manufacturing has the replacement that you need to get the job done!Ultraviolet lighting replacement bulbHighest quality materials are used to produce high-end suppliesProvides the best environment for your aquatic life10 watts9,000 hour bulbDanner Manufacturing's replacement ultra violet 10 watt bulb is rated to provide up to 9,000 hours of use. This product is using the highest quality materials to provide the best environment for your aquatic life. It is recommended to replace your bulbs on a yearly basis, as bulbs can lose their effectiveness over time. So replace your bulbs and eliminate that pesky algae in your pond today with Danner Manufacturing's bulbs!