uv light in saltwater

You will not need a UV light in a reef tank if it is set up properly the first time, Qt will stop you diseases, strong Skimming will keep unwanted algae down. It is much bette spending the money on a highly efficient skimmer rather than on a UV light.
 
If you had extra money to spend and already had the things mysis mentioned, I would say its a good idea. But not unless you're other equipment was good.
 
I removed my UV light from my reef tank based on advice I got here. It kills the plankton and other micro-organisms that the corals feed on. For a FOWLR I guess it'd be a good idea (with the caveats in the above posts that other equipment is more important).
 
UV is benifical with the break down of inorganics that create algae. But I would buy a good skimmer way before a UV steralizer, I would kinda want that set up a certain way on a overflow, which isn't possible in my setup.
 
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