To UV or not to UV?

[rmiga13]

What is everyones take on UV sterizer's? What are the advantages or disadvantages?

[Carlos]

Unless you have a really high-powered UV sterilizer with very very low water flow, I don't think they are much use.

JMHO,

Carlos

[Blakethebug]

IMO they dont have any place in a reef tank. FO systems, maybe, but in a reef they're just gonna kill off all the pods and other good stuff that you need for a reef tank.

[usmc121581]

I bought one for my reef 2 years ago. I have used it maybe a total of 5 days if that. That was only because my hippo tang had ick.

[greenbean36191]

Pros: They help break down organics in the water making it clearer and helping reduce algae.

Cons: They need a lot of maintenance and use electricity for the minor benefit they provide.

They won't kill off all of your pods, bacteria, ich, or anything else that happens to be in the water. On recirculating systems, controlled tests have shown that their impacts on life in the water are essentially unmeasurable regardless of how big they are and how you run the water through.

[Fmxmatt]

Myself, along with many others I know, swear by them for ich reduction in Reef tanks.

U can say this and that all you want, the proof is in the pudding

[greenbean36191]

Here's a list of a few articles that looked at the effectiveness of UV under controlled conditions on recirculating systems. They look at a variety of protozoans, bacteria, and fungal pathogens. In nearly all of them, pathogen mortality coming from the sterilizer was at or near 100% yet they all found that there was either no reduction in the overall population of pathogens in the tank or no reduction in infection rates vs. controls. The only reduction in infections seen can be attributed to acquired immunity and occurs with or without the sterilizer.

Spotte, S. and Adams, G. 1981. Pathogen Reduction in Closed Aquaculture Systems by UV Radiation: Fact or Artifact? MEPS 6: 295-298.

Herald, E. S., Dempster, R. P, Hunt. M. 1970. Ultraviolet sterilization of aquarium water. In: Hayen, W. (ed.) Aquarium design criteria (Spec ed.), Drum and Croaker, U S Department of the Interior, Washington, DC. 57-71

Bullock. G. L.. Stuckey, H. M. 1977. Ultraviolet treatment of water for destruction of five gram-negative bacteria pathogenic to fishes. J. Fish. Res. Bd Can. 34: 1244-1249

Spotte, S., Buck, J. D. 1981. The efficacy of UV irradiation in the microbial disinfection of marine mammal water J. Wildl. Dis. 17: 11-16

Spanier, E. 1978. Preliminary trials with an ultraviolet liquid sterilizer. Aquaculture 14: 75-84

Gratzek, J.B., Gilbert, J.P., Lohr, A.L., Shotts, E.B. Jr., Brown, J. 1983. Ultraviolet light control of Ichthyophthirius multifiliis (Fouquet) in a closed fish culture recirculation system. J. Fish. Dis. 6:2 145-153.

[cd77]

Originally posted by Fmxmatt
Myself, along with many others I know, swear by them for ich reduction in Reef tanks.

U can say this and that all you want, the proof is in the pudding

Looks like greenbean has all the pudding.

[Fmxmatt]

Just because someone wrote it down and has a PHD in something doesn't always make it so.

When I said the proof is in the pudding, I meant that myself, along with many others, have found that despite what some guy who has some certification said, the UV steriliser was beneficial to the reduction of whitespot.

[cd77]

So, what were your parameters when you tested the effects of ultraviolet radiation on Ich? What mortality rate did you observe? What equipment did you use to test? Your eyes? What variables were you able to eliminate as other possible causes of Ich reduction? None?

I've had FW tanks for years -- never observed Ich or had a fish die of Ich. Not once. Every single tank was a glass tank though, and not acrylic -- never used UV. Is it fair to swear by the use of glass vs. acrylic as a means of Ich control? Or, perhaps I can state that not using a UV sterilizer is beneficial to the reduction of Ich.

See the issue here?

Just because someone wrote it down and has a PHD in something doesn't always make it so.

Agreed; however it's not the alphabet soup behind the researcher's name that give the research results validity; it's the fact these are controlled experiments employing the scientific method -- not just a few hobbyist's conclusion based simply on correlation in an uncontrolled environment.

I hope it's clear that I'm not trying to start a flame war here.

[m2434]

Originally posted by Fmxmatt
Just because someone wrote it down and has a PHD in something doesn't always make it so.

When I said the proof is in the pudding, I meant that myself, along with many others, have found that despite what some guy who has some certification said, the UV steriliser was beneficial to the reduction of whitespot.

So I should instead trust some guy without a certification?

Science is not infallible, but to be published you need to get though extensive peer-review, to get funding in the first place, then go though extensive peer-review to get published and then your work is critiqued by everyone reading your article. Not to say you should believe everything you read, but if there is a flaw, plenty of peers (or competitors depending on how you look at it) will be there to point it out... In other words, UV has been under the microscope for some time, if there was a benifit to UV, someone would have published already..