UV sterilizers

[scubadude]

Just wandering who is using them and what size of sterilizer they are using, as well as the size of their tank? Do you keep it on 24/7 or just when you suspect a problem? How much flow you have running through them? What name brand you use? How often do you clean yours and how often do you replace your bulb? and Is yours on a quarantine tank or your main tank? Have you noticed benefits...please feel free to explain in detail

[Samper]

I use one, it's 4 watts with a mj 400 running it. I keep it on 24/7 for the most part turning it off maybe once or twice a month for a day or two. I don't think it does anything being that small.

I actually just took it apart yesterday to clean everything and can't for the life of me get the bulb back in, might throw it out.

[scubadude]

Chuck what type of sterilizer is it?

[Samper]

http://www.drsfostersmith.com/produc...7&N=2004+22789


The guy that got me in this hobby told me it was a hawaiian marine unit that they were top of the line and I had to have it. Not knowing any better at the time I bought it from him for $100. If you check out the first posts I had on this site he had me all screwed up from the setup to livestock. We don't speak anymore cause of that and the last time I saw him his system looked like crap.

Oh yeah this was the same guy that told me if I start reading the forums and stop listening to him my system would go downhill. I've seen quite the opposite.
THANKS REEFLAND

[Brett A Ross]

I have a 8w (cant remember the brand ) running on my 75gal fowlr. After I added my CB he developed a case of ick. I do not have a qt tank (no place for it) so I bought the UV out of desperation. I fed garlic and ginger in my daily feedings. The infection cleared up. I must add I FW dipped the CB so I'm not sure what did the job. From the research I have done here and on RC I am inclined to believe that good water quality probably helped more than the UV and garlic treatments. with all of this in mind it has been 2 months since the original outbreak. The infection never spread to my other fish or reappear on my CB. I think the idea that the UV keeps the ick at a level the fish can fight off with good water quality has merit. I will keep using it.

[middlemark]

I've thought about one, very interested what folks have to say about them.

Great topic.

[Ninong]

Just wandering who is using them and what size of sterilizer they are using, as well as the size of their tank? Do you keep it on 24/7 or just when you suspect a problem? How much flow you have running through them? What name brand you use? How often do you clean yours and how often do you replace your bulb? and Is yours on a quarantine tank or your main tank? Have you noticed benefits...please feel free to explain in detail

IMO Aqua-Ultraviolet makes the best UV units. http://www.aquaultraviolet.com/

I have a 40w unit (without wiper) than I have used on an outdoor pond. The lamp has to be replaced about once a year. How often you need to clean it depends on how energetic you are and the type of water running through it. Now that they offer them with built-in wipers, you would be able to clean it a whole lot easier. In most applications, they need to be cleaned at least once a month.

Here is their UV sizing chart:
http://www.aquaultraviolet.com/sizing.html

Don't confuse maximum flow with having anything to do with recommended flow. Maximum flow is just the maximum physical flow that the unit can handle. The rate of flow depends on what you are trying to accomplish and whether you are running it on a freshwater pond or a saltwater aquarium. You can run a lot more water through the tube if all you are trying to do is clarify pond water. If you are trying to kill anything other than algae, you will have to slow down the rate of flow to increase your dwell time.

Notice that a saltwater aquarium requires a MUCH larger unit per volume of water than a freshwater pond. I think that new 114w unit with wipers (two 57w lamps) sounds like a good one for a reef tank around 300-350 gallons.

The UV unit needs to be plumbed so that you can totally control the flow through it and cut it off completely for cleaning and lamp replacement. In a pond, you would place the UV unit between the return pump and the outflow to the pond and you would plumb it so that it is a bypass line with a ball valve (or gate valve) regulating the flow through the UV.

I used to think that I would never consider a UV unit on a reef tank but I have sort of changed my mind after seeing so many gorgeous, very large reef tanks (e.g., Steve Weast's) that are running them. I think this falls into somewhat the same category as ozone -- not something you would run out and buy for your everyday, run of the mill average sized reef tank but something you might want to consider for tanks of 300 gallons and up. Nobody says you have to run the thing 24/7. I now think that if I were to set up a very expensive, large reef tank, I would want to install a UV unit just in case I wanted to run it. I'm sure I would use it, I'm just now sure how often I would use it.

Look at it this way: If you have upwards of $30,000 invested in your system, you may as well go all out and stick everything available on it in case you decide you want to run it. People with large tanks (500 gallons and up) who run UVs swear by them. Typical claims are along the lines of, "I have never experienced RTN in my tank and that's because I'm running UV and ozone" or "I have never had a problem with Cryptocaryon irritans, Brooklynella hostilis or Amyloodinium ocellatum and that's thanks to my UV sterilizer."

Food for thought.

Just remember the basics: Nothing is killed unless it passes through the UV tube. Nothing is killed unless the dosage is high enough (sufficient dwell time and adequate wattage). Whatever does pass through the UV tube will be exposed and killed if the dosage is sufficient. That includes the good, the bad and the ugly. The turnover rate has to be sufficient to ensure repeated passes per hour depending on whether you're running it on a saltwater aquarium or a pond. For a saltwater aquarium, the recommended turnover rate is 4-5 times the tank volume. That's why they recommend the 114w unit for a maximum of 325 gallons of saltwater (4x325=1300 gph, which yields 90,000 µw/cm² -- the dosage required to kill free-swimming theronts of Cryptocaryon irritans). Obviously only the theronts that pass through the UV tube will be killed. That means that if they manage to find a host fish to attach to without passing through the UV unit, they are home free. Chances are that if your turnover rate is at least four times per hour, you will be able to run most of them through the UV before they find a fish to call home, but it's not 100% certain that all of them will go though the little house of horrors first.

Number One reason for running a UV: They kill everything -- the good, the bad and the ugly.

Number One reason for NOT running a UV: Same as above.

Or to put it another way, some people argue in favor of running a "sterile" system, while other people argue against running a sterile system. I have seen the hypothesis put forth that an overly sterile environment is unnatural and possibly detrimental to the functionality of the immune systems of the animals kept in such an environment. The counter argument to that hypothesis would be the experience of people like Steve Weast and others who are running UV units without any unexplained health problems observed in their fish and inverts. In fact, they seem to have far fewer health problems than others who are running without UV units.

[scubadude]

I used to think that I would never consider a UV unit on a reef tank but I have sort of changed my mind after seeing so many gorgeous, very large reef tanks (e.g., Steve Weast's) that are running them. I think this falls into somewhat the same category as ozone -- not something you would run out and buy for your everyday, run of the mill average sized reef tank but something you might want to consider for tanks of 300 gallons and up.

First off thanx Ninong ;)
The statement of above fits my exact feeling too. If you are feeling equally to the task could you give us the lowdown on Ozonizers as well, I mean there is a difference between the two right?

[Ninong]

First off thanx Ninong ;)
The statement of above fits my exact feeling too. If you are feeling equally to the task could you give us the lowdown on Ozonizers as well, I mean there is a difference between the two right?

Yes, there is a major difference between UV sterilizers and ozone. A UV sterilizer is nothing more than a lamp that emits light at 254 nm (VERY dangerous UV-C). The water flows through the tube and is exposed to the enclosed UV lamp.

Ozone is a molecule of oxygen that is highly reactive and unstable. It has three oxygen atoms instead of the usual two. It has long been used as a disinfectant in water supplies. Like ultraviolet radiation, it can kill microbes, viruses and protozoa. In marine aquaria, it is usually injected into the protein skimmer. My skimmer, for example, could have been used with ozone if I had specified in advance that that was my intention. In which case Jeff would have supplied it with a carbon filter in the collection cup lid to trap any escaping ozone. Ozone is not good for you. It is an extreme irritant. Which is why smog is so nasty -- it contains ozone. Most ozone is high in the atmosphere, the ozone layer, where it protects us from harmful radiation from the sun. When the notorious ozone hole shifts over inhabited areas of South America, skin cancers go up. But that's a bit off-topic.

Steve Weast is using ozone on his system. I'm not sure how often he runs it but you could probably find out. Ozone is very common in large public aquaria because they want to keep their systems free of pathogens.

The same arguments that can be made either for or against the use of UV sterilizers can be made for or against ozone.

[Bald Eagle]

Hello, everybody. This is my first post on this Forum. On the subject of U.V.'s, I have seen fantastic set-ups with and without them. I can only speak on my own expericence using U.V.'s. I have had them running on my tanks for yrs. All i have seen on my tanks are positive results. Very healthy colorful fish. Very healthy and colorful corals. I have had a colony of reproducing plates in my tank for 2 yrs. now, and it still puts out babies all the time. all my Acros are extremely colorful. My LPS's are doing extremely well. I have not seen one downside to this approach, whatsoever. My leathers are trying to grow out of the tank.

[reefsus]

25w emporer aquatics unit.

[reefsus]

Uv's does not usually kill everything that passes through them, they will usually only kills stuff that is easy to penetrate like phytonplankton. Most of the time when larger stuff like zooplankton and macro inverts pass through they usually make it through.

But you also have to remember, only stuff that spends a lot of time in the water column will get killed. A lot of zooplankton life stays put in the rockwork.

Ozone on the other hand probably do kill just about everything that passes through it, but there is a lot less that will pass through it.

[Ninong]

Uv's does not usually kill everything that passes through them, they will usually only kills stuff that is easy to penetrate like phytonplankton. Most of the time when larger stuff like zooplankton and macro inverts pass through they usually make it through.

I think it's all a matter of dosage. You can kill just about anything if the dosage is high enough. Just as metal halide lamps vary in efficiency from one brand to another, so do UV lamps: http://www.aquaultraviolet.com/uvtest.html

Some 25w UV lamps are twice as powerful as other 25w UV lamps. As long as the aquarium is no larger than 90 gallons, I think a good 25w UV lamp with the flow cut down to no more than 400 gph should be able to do the job. That assumes the lamp is not worn out and that it is clean. If something is not killed outright on the very first pass through the unit, it should be killed after repeated passes.

There is nothing you can do about an organism that manages to avoid going through the UV sterilizer but anything can be killed if the unit is powerful enough. Aqua-Ultraviolet makes a 240w unit that uses six 40w lamps and they are working on a 2,000w unit. There are a lot of nice commercial units out there that are 440w and 660w.

My 40w Aqua-UltraViolet was undersized for the size of the pond I was running it on but it still did an excellent job of keeping the water clear. If I were to hook it up to my 120-gal reef tank, I'm confident it would be sufficient to kill such pests as Cryptocaryon irritans providing the theront passed through the tube.

[reefsus]

Hmmm... i wonder if that test is true. Ive always heard emporer aquatics to be the best UV brand, and it seems a little fishy since the company of the aqua is doing the test.

[Ninong]

First off thanx Ninong ;)
The statement of above fits my exact feeling too. If you are feeling equally to the task could you give us the lowdown on Ozonizers as well, I mean there is a difference between the two right?

Rocky,

I may not have addressed your question about the differences between ozonizers and UV sterilizers fully in previous response because I wasn't thinking about UV ozonizers at the time.

Ozone can be either CD or UV. CD = corona discharge, electrical generation of ozone and UV = ultraviolet (185 nm) generation of ozone. The ultraviolet ozonizer utilizes an ultraviolet lamp in the 185 nm wavelength to break up the O2 molecules as air passes over the lamp. The resulting O1 atoms quickly regroup into O3 (ozone) molecules, which are then injected into the water. I really haven't gotten into ozone generation very much because I'm not ready to consider that yet for my next system. I believe CD ozonizers are more efficient. I guess I'll have to look into it more thoroughly before I start finalizing my plans so that I can make an informed decision.

Here is an article http://www.wetwebmedia.com/AqBizSubWebIndex/bizuvs.htm that Robert Fenner has on his website www.wetwebmedia.com wherein he discusses UV. Keep in mind that he likes ozone and, in general, does not like UV for the average reef aquarium hobbyist. I'm sure he favors both for very large commercial systems. I know he has an ozone article in there somewhere because I remember reading one of his articles a long, long time ago that covered both ozone and UV in the same article.

Also, for some reason Fenner states that UV and near UV ranges from 295-400 nm. That statement is incorrect because UV-C is 280 nm and below. UV sterilizers use a 254 nm lamp and ozone generators that use the UV method utilize a 185 nm lamp. (P.S. -- I think the ultraviolet range starts somewhere around 100 nm but I haven't bothered to look that up. Yet. )

Based on the little research that I have done on both ozone and UV sterilizers, I believe that their benefits outweigh their obvious drawbacks for very large systems, such as Steve Weast's new 850-gal reef tank. Or, to put it another way, I'm reluctant to second guess someone as anal as Steve when it comes to the spare-no-expense version of setting up a large reef aquarium. Maybe we should send him a link to this thread so that he can offer his input.

P.S. -- Here is a link to Fenner's article discussing both UV and ozone: http://www.wetwebmedia.com/marphysf.htm

[Ninong]

Looks like I was off on the full range of ultraviolet radiation. Seems like it is everything above x-rays all the way up to 400 nm. That makes it anything from 1 nm to 400 nm: http://csep10.phys.utk.edu/astr162/l.../spectrum.html Hmmm... I just noticed that they say The following table gives approximate wavelengths, frequencies, and energies for selected regions of the electromagnetic spectrum.

Maybe "approximate" could be 380 nm?

I think the range from 380-400 nm is considered near ultraviolet. Usually you see ultraviolet described as "anything below 380 nm." Now I know why.

[steveweast]

UV........................Aqua single bulb 200watt
wiper unit ?.............no, they tend to leak and take up too much room
flow rate................around 2500 - 3000 gph
cleaning.................clean quartz sleeve every 4 - 6 weeks
bulb replacement......every 12 months
duration..................24/7

reason why ?...........I have a very deep tank ( 90 inches from front to back). Without the use of UV, the tank would appear cloudy all the time.....just look at the average tank through the side panel.....they usually look far less clear than when viewed from the front. My tank generally appears as if there is no water there....and this with about 60 fish. The high clarity also improves light penetration. The UV does kill good organisms as well as the bad....but, I feel that the bad stuff is worse than the good stuff is good.....besides, there's still a significant plankton population that emerges from the rocks each night.


Ozone

I used to run it through two of my four Precision Marine skimmers. The two with the ozone would always yield a much more concentrated skimmate. I'm now running a single very large Deltec skimmer....but, I'm not running ozone yet. With the four seperate needle wheel pumps and the small air intakes for each pump....it's not that easy to inject ozone. I may modify the unit to be able to add ozone more readily. The only negative with running ozone is having to keep an eye on the redox.....yes, you can have a probe control the delivery....but, I generally distrust all but temperature probes.

[Ninong]

Steve,

Thanks for your input.

[steveweast]

OK...you guys made me realize that I was being a lazy sob. Today, I sat down and made an air manifold that works with my Deltec skimmer and activated my Ozotech ozone generator once again. I'm currently running about 250mg/hr. It's something that I should have done sooner....oh wel, it's done now.