Do I Need a UV Sterilizer?

[fishtanktenderfoot]

As my tank cycled, I went through a bout of algae. I addressed it by reducing my lights and thoroughly cleaning. It hasn't returned and my tank is fully cycled now, but it did get me to research UV sterilizers. Aside from algae, I understand the right sterilizer can kill bacteria if I set it up with proper flow, etc.

My question is, does it work? By work, I mean for those of you who have one set up to kill bacteria, does it eliminate risk of ich or other fish problems? Is it a good preventative investment? I'm on the fence whether I should buy one, and I'm wondering if it will help me avoid a visit to the emergency room?!

And a follow up question, do I need to operate it all the time? Or can I use it on a schedule where I operate it for a few days and then not for a few days? Can I use it in my aging barrel while I age new water for 24 hrs? I'm trying to figure out if it's better to treat the water before it hits my main tank or if that even makes any sense?

Sam

[Keith Perkins]

My understanding is that they do in fact work if you purchase the proper size and have the flow right. However, to date, there's still no substitution for large frequent WCs and good husbandry. You'll find the vast vast majority of experienced people around here don't use UV sterilizers and generally stay out of the emergency room. Personally I'd save your money and buy better fish with it. :)

[adapted]

You could definitely use one in your aging barrel if you are using well water that is known to contain microbes. Do some research and avoid buying one of the units that can only do clarification rather than level one sterilization.

I 've been using a 25 watt unit with good dwell time and while I can't swear it has made significant difference I have no complaints.

[fishtanktenderfoot]

So is the feeling that UV sterilizers can't do anything that large water changes can do? I'm not on well water, I'm on city water that uses chlorine. I age my water to burn off the chlorine, so maybe trying to kill stuff in my aging barrel doesn't make any sense after all. Adapted - is yours set up to run all the time?

[discuspaul]

I don't feel that any discus-keeper really NEEDS a UV sterilizer.

But having said that, I've used UV's over the years in several tanks, including 2 years straight in a planted discus tank, running it 24/7, because I believe this equipment has many side benefits taken as a whole (albeit no single one being overly significant), including picking up and destroying any free-floating algae spores, improving flow and water circulation, keeping the surface free of protein film, and assisting with oxygenation. As for destroying pathogens with the correct flow through the UV, I've seen no evidence of that, apart from the fact that all the mid-sized younger discus I had in the tank for those 2 years remained healthy & thriving in the planted set-up.
During those 2 years, I sold or re-homed at least 3 sets of sub-adult fish, replacing them each time with another batch of similar-sized fish for testing grow-out in a planted environment.
Large, frequent wcs were always a priority though.

[kris2341]

just thought i'd put in on this too, I generally am a person that believes a UV sterilizer is not really needed in any optimal setup with strong fish. But if you get fish from different sources, they could come down with problems related to disease.

I don't know how accurate this is, but I generally avoid UV sterilizers on the basis that growing fish in an environment that is too clean, especially from egg to adult, makes it so that they cant really build up immunity properly. I only whip them out when there is a problem that I am at a loss to fix.

I remember raising some african cichlid fry in a tank to try and see how good i can grow them and wanted to use a UV sterilizer to keep them from getting attacked by fungus and the like while i fed them heavily and did maintenance. They got big, looked great, but when it came to putting them in the cichlid pond(yes it is a heated tropical fish pond), practically all of them died to different ailments.

Ever since then, i went all natural...

[DonMD]

I believe this equipment has many side benefits taken as a whole (albeit no single one being overly significant), including picking up and destroying any free-floating algae spores

I think this is the one huge benefit from UV, that it helps eliminate "green water." I use one on my planted angel tank that gets a water change, if it's lucky, once every three weeks. On my discus tanks, it's nothing but tons of fresh water, and no plants. But I'm pleased how it works on my angel tank . . .

[kris2341]

I think the use of UV as a clarifier is the optimal approach for most aquariums, but as long as the fish are strong genetically and have built up resistance to common pathogens and parasites, it should not matter how strong of a UV you use on a tank.

The only scenarios where I would not recommend UV is where free floating organisms are beneficial to the system such as larval ghost shrimp feeding on algae spores in the water, and when raising freshly hatched fry so they can build up their immunity to disease.

If the fish are strong and the aquarist is careful with their selection, the use of UV for antibacterial, antiparasitic, and antiviral purposes is a bit redundant but it doesn't hurt once the fish are old and have strong immune systems.