Review on 🐠 Aquarium Clean Light - UV Sanitizer for Algae Bloom, 9W & 11W with Timer - Submersible Waterproof Lamp for Fish Tank, Pond, Sump Swim Pool - Water Clean Green Clear Waterproof Lamp by Mary Reed

This lamp works very well. It will clean the tank of green water (algae in the water column) in 2-5 days depending on how often you use it. Please use common sense, DO NOT place an open UV lamp in your tank and then wonder why your fish died! This is ultraviolet light, and it harms any living organism that is directly or nearby exposed to it. Simply place this bulb in a separate filter or plug it into your filter's inlet pipe and it will safely kill any algae and bacteria present in the water. I assure you that this lamp works well and I have used it for countless hours without a single problem in several of our aquariums.