I have debated the same issue for quit some time and most likely add a UV on my new tank design. Lets see-- a couple tangs, a couple clowns, firefish, anthias, gobies, flamehawk, blenny, wrasses, etc-- all equal a lot of money and attachment. If I can create a better environment for them to live in and not perish (which would mean me too replace more fish instead of buying more corals) why would I not do that. In someways it is almost unresponsible not to do it. IMO.