The first fry from L260

[Lihn]

I already mentioned that I doubted whether your fish had Ich but just for the sake of discussion, if you hope that UV will protect your fish from that disease, consider this:
Most UV ratings are for how much UV radiation with a wave length of 253.7 nanometers are required to kill algae. It takes 22,000 microwatts/cm2 to kill Chorella algae.
It takes 336,000 microwatts/cm2 to kill Ichthyophthrius tomites.
What this means is that most aquarists use UV units which are grossly under powered to have any real effect against most fish diseases. Furthermore, a typical UV source loses 40% of its effects after 6 months. To use an effective level of UV, one needs to seriously up the power. This soon reaches a very expensive level to fight that which can prevented by strict quarantine procedures and those are much cheaper than relying on UV, imho. Just something to consider before investing in UV.
Information is from the book, Aquaculture Engineering, sometimes referred to as the aquaculture "bible", Frederick W. Wheaton, reprint 1985. Hard cover, 728 pages. $99.25 from http://www.aquaticeco.com. Cat. # WQB3

Yeah, I need some more power at the UV to kill the parasites.
But this was my only possibility to try just one more thing to stop the disease..

[apistomaster]

There have been some occasions when I would have like to have a UV unit for some fish breeding project instead of using chemical antibacterial or antifungal chemicals. Especially with some of my Characin breeding projects.
I am not anti-UV but I did want to share with everyone that to sterilize aquarium water takes a much higher wattage than a typical manufacturers' published recommended power levels.

[PseudaSmart]

Don't go crazy on the numbers. Most numbers stated for uv are for 100% kill on the first pass. With the high tank turnover many of us use the lower wattagee is fine. I run 8 watt uv on my 180gals and 25 watts uv on my 300gal without any problem. When you add uv to a system you can see the water become crystal clear in a few days and any leftover food does not fungus right away in fry tanks. It also reducessd algae in my planted tank. I have had uv for 5 years and I go 1 year between changing bulbs.

It may not cure everything but it helps!