The Aquatop UVP-13 submersible UV sterilizing pump is a new and innovative method for eradicating and controlling free-floating micro-organisms as well as disease causing pathogens. Unlike typical UV sterilizing systems, the UVP-13 requires no special plumbing and is easy to use and maintain. Simply place the UVP-13 directly into your tank or sump system up to the waterline. The built in pump will draw water in, running it past the 13 watt UV bulb. The UV light will sterilize and clarify, producing crystal clear water.
When I first received it I could not get it to lite the uv indicator light and discovered that du to water and color reflection its really hard to see. Maybe they could put the light elsewhere or change the color. I would have never expected the great result if I had not been reading about green tank water. This unite cleaned my tank overnight and is now crystal clean. great product and very good pricing for what it gives you in return. Highly recommend this uv system to anyone.If you don't have one get one you will be very glad you did.5 STARS