green water

[Marcus K]

My green water was almost gone when I started to get my lights back up to normal on times and my water is starting to go green again. I am fed up with the green and I am looking into a UV sterilizer. I have heard that you only need the once in a while and was wondering if I could get away with a 9W coralife from J and L. Would it be strong enough on a 90gal to clean the water? Thanks Marcus