UV sterilizer as an insurance policy?

[Dinyar]

I have a 125 gal African tank containing lots of expensive and hard-to-find fish. I have a recurring nightmare of a disease outbreak in the tank. I recognize that good fish keeping practice is the best way to keep nasty critters away. Still, I have lots of tanks, buy a fair number of new fish, and from time to time, experience some kind of disease problem. For example, in my S. American tank I recently lost a Pimelodus ornatus and a Pseudocetopsis sp. to what may have been some kind of gill fluke.

I was thinking of installing a UV sterilizer on the 125 gal as an additional layer of defense against a disease outbreak. I've been researching this issue for at least 6 months, and still can't figure out if it would be a good idea.

On the con side: (1) lots of knowledgeable people I've talked to have said that if you have good fish keeping practices to begin with, a UV sterilizer doesn't buy you much additional protection; (2) they're somewhat expensive, especially when you include the long-term cost of replacing bulbs, electricity, etc., plus it's one more device that can fail; (3) some claim that fish (like all animals) are better off with some low level exposure to pathogens to which they can build resisitance, and therefore too sterile an environment is actually bad for long-term fish health.

On the plus side: (1) it would appear that in the short to medium term, appropriately sized and maintained UV sterilizers DO serve to limit the incidence of most ectoparasites and some pathogenic bacteria; (2) relative to the potential cost of a major disease outbreak, the long-term cost of the sterilizer is small; (3) they have the side benefit of reducing algae and improving water clarity.

Now my questions: (1) do any of you use UV sterilizers?; (2) if so, how do you rate your overall personal experience with them?; (3) can you comment on the pros and cons above?

Thanks,
Dinyar

[König Löwe]

I have no experience with UV-filters, but i am wondering if it could not be usefull to have it ready and installed, then you can turn it on and run it if you suspect a disease breakout.

[smilingSyno]

I have a 150g tank heavily loaded with catfish, i.e. most synodnotis...
feather fins (10), Alberti (5), lace (1), angelicus (2), (2) hammerheads,
and (10) USDers....
As well as 4 hopols, and 3 plecos..... oh yea, an American catfish and
an Asian Bubblebee catfish.....
I run a wet/dry bio-rocker on the sump and have 2 emp400......
I do a 25g water change out once a week if not sooner and I vaccum
it each time....

I change out the filters on the emps twice a week... They get very
dirty fast... about the same for the filter above the sump as well
as 2 media baskets on 402 powerheads I have submerged.....

I put a UV on the sump..... it kept the algae down when I ran PC
lights on the tank... but since I just put a couple cheap lights under
the hood so save on power (catfish dont like the bright lights anyway)
and algae would not be a problem, I've kept the UV running for just
that added measure as you have stated.... Its been on their about
8 months now and I have an extra bulb if I ever get around to changing
it.
I have never had any problems with any of the fish ...... except...
I've noticed that one of my featherfins has a blueish color eye.....
have no idea what could be the problem, but I have not taken
any other measures except adding Melafix to the tank on occasions.