My lfs did a pretty good job of convincing me to go with a uv light on my tank. I have a very strict maintenance schedule with my tank and water parameters are always in line with where they should be. I have always thougt my water looked great and very clean and clear. Until I added the UV light. It is a 9 watt turbo twist that my lfs recommended I not buy from them because I could find it cheaper elsewhere. I did, 73.99 from That Pet Place compared to 99.00 from foster and smith which was the next cheapest. After getting it plumbed inline with my Eheim 2213, I also use an Eheim Ecco 2232, in just a few hours I already noticed a difference in water clarity. My wife looked at the tank and said it looks like there is no water in there. I plan on running it on a timer at night for a few hours. Just thought I would share that info with you because I really never thought my water could be clearer then it was.