I have an Aquanetics 8 watt UV that's had the bulb replaced 2x in 18 years. Works fine.
I don't used it 24/7, That doesn't help. Once a week at most.
Folks want too many fish, don't want to do water changes etc. A UV will beat back some of the issues there, not much IME.
I have not used medication of _any sort_ for a fish in close to 16 years. I have never lost a fish, I've had them come in with ich etc, but it went away in about 3-4 days. Suicidial jumpers but none due to other causes.
Basically, I've never needed any medication. I've pulled many critters and plants from the wild. All my plants and fish I now have all came from the wild. I rinsed them with tap for a few minutes(the plants) and acclimated.
No quarantine to speak of. With expensive fish, I will quarantine.
Good stocking levels, good variety based foods(not just one thing every day forever) without live foods, except for brine on occasion, 50% weekly water changes, healthy plant growth, good current.
A UV is good to have for ocassional use for Fry tanks, certain special applications but I find them not very useful as an intergral part of the system.
I add one on only for a couple of days for a badly infested algae tank and that's about all. I don't add it permantly to any system.
It's like leaving the lights on in your house when your not home, it won't hurt, it'll just cost you money $ for electric and more frequent bulb replacements.....
Turn it on only when you need it.
Regards,
Tom Barr