Review on Roxin 5W 7W 13W UVC Aquarium Green Clean Light Algae Bloom Clear Lamp - Aquatic Water Cleaner for Pond Fish Tank, Sump, Swimpool - Waterproof UV Sterilizer by Laurel Rohr

UV sterilizer worked as expected. Looking at some of these reviews, they either don't know how to use it, haven't read the instructions that came with it, or both. You don't use it as a hood for your aquarium, you don't put it directly in the aquarium, and you don't turn it on 24 hours a day, 7 days a week, year-round. You should build and fence or use a sump system for a few hours every few days as needed. Direct UV exposure from fish will fill it up, continued use will kill any bacteria in your tank and it's bad for the human eye too. Proper use gives positive results. My aquarium is usually fairly clean and well cared for to maintain a healthy environment for the fish I keep. However, when I saw the cost of this product, I decided to order it. The day I placed the order I started overfeeding the fish a bit, left the 6500K light on for extended periods and skipped two water changes only to have the water cloudy with free floating algae. Then when the UV sterilizer arrived I went to the local hardware store to buy PVC tubing, PVC fittings, some PVC glue and a small fountain pump. Gathered the parts needed to house the UV lamp assembly, attached the tubing from the fountain pump to the PVC housing I made and ran for three hours. The results were great. The water cleared and the fish began to swim more actively than before. Without a doubt, the product does what it is supposed to do when used properly. I will be getting a few more for my fish room once it is installed again as a weekly preventive maintenance routine to reduce free floating algae and various bacteria that can cause infections in fish. This will help protect against infections such as ichthyophthyriasis, various helminths, etc. Using a UV sterilizer is a much better option than using various chemicals available on the market. I am attaching two photos, one before UV treatment and one after. It is obvious which before and after photo. *edited to correct a spelling mistake*