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 Rachel Streater

I actually use this for a sterilizer not an aquarium but the actual use and end use is pretty much the same as its purpose. As far as I can tell (without looking at it directly, of course) it's definitely emitting a lot of light in the 254.3nm range, as intended. The 11w version is quite strong (probably a lot more than I really want, but I needed something that was readily available) and definitely produces a pretty strong smell. I'm not sure, but it might be missing part of the 185nm band and producing some ozone. It's actually great for disinfecting, but if it produces some ozone it might do poorly as an active disinfectant for something like an aquarium (because it might then produce too much ozone in the water for the fish). It is advisable to test it thoroughly before using it as an exterior cleaner or anything like that. If the fish is taken out of the tank and you wait a bit before putting it back in, everything should be fine. As a disinfectant, it's probably great. I won't deny that I don't have the tools to test the exact light output, but the smell alone is great proof that it definitely works and is capable of creating such an airborne effect. In fact, I would advise anyone planning something like this to get the smaller 7W version. Remember that UV-C is very bad for your eyes and skin. So if someone intends to do the same, they should limit themselves to something or even another space. This is not a sanitizing pen (and should even be used with extreme caution) and should not be used in this way. It's total UV-C light everywhere. I have a subtlety that goes beyond mere subtlety. The cable is very uncomfortable. The part of the cable from the mains to the PSU is very short, the PSU is too close to it and it is very inconvenient to deal with it (the switch is obviously on the PSU). Then from there it's still a pretty short cable from the PSU to the lamp itself. I think the power cord to the PSU should not only have been longer, it should have been one of those standard detachable cords (which would give people the option of swapping out 3rd party cords of any length ). If you use it for its official purpose, I think it can be very inconvenient. At least the cable from the power supply to the lamp itself is long.