This Green Killing Machine (GKM) UV purifier is ideal to help polish the water creating a crystal clear, pathogen free aquarium. The item comes with its own pump, is fully submersible in your aquarium or filter sump, plus a mini LED light lets you know when the UV bulb needs to be changed for effectiveness. The water passes through the chamber in a zigzag motion to ensure maximum time of water contact with the UV light. The UV light is concealed inside the black chamber for your protection, where the water will pass through killing any algae spores and pathogens, which may be present within your aquarium. Reduces the potential of fish becoming sick. The small sponge needs to be rinsed thoroughly every week or two, dependent on water clarity.The UV bulbs need to be replaced when the LED light turns off on your monitor box, or at approximately 2000hrs of usage. Suitable in both fresh and salt water aquariums. 24watt model treats 200-450L aquariums. Replacement UV are available here. Reviews There are no reviews yet. Be the first to review “AA Aquarium GKM Internal UV with Power Head (up to 450L)” Cancel replyYour email address will not be published. Required fields are marked *Your rating * Rate… Perfect Good Average Not that bad Very poor Your review *Name * Email * Save my name, email, and website in this browser for the next time I comment.