I know that UV Sterilizers are good for controling green water...however, how effective are they at preventing algae from growing on the surfaces of the tank, rocks, etc...???
The following URL will provide you with the product description of one...
http://www.aa-aquarium.com/NewProduct2.php?id=156&line_id=&level=3
The following URL will provide you with the product description of one...
http://www.aa-aquarium.com/NewProduct2.php?id=156&line_id=&level=3