Equipment of the Week: UV Sterilizer

revhtree · Jul 13, 2012

When used in conjunction with proper fish-keeping practices, an ultraviolet sterilizer is a great way to help protect aquarium inhabitants from potentially harmful microorganisms. Ultraviolet sterilizers use a special fluorescent lamp that emits light at a wavelength of 253.7 nanometers. Aquarium water pumped through the UV chamber is exposed to this UV light and is irradiated. Free-floating microorganisms in the passing water are affected by the UV light and are no longer able to multiply. Through continual use, UV sterilizers can help manage water quality issues due to microorganisms such as bacteria, algae, and parasites.

Proper flow rate through the UV chamber determines the effectiveness and use of a UV unit. Set at different flow rates, a UV sterilizer can be used effectively against bacteria, algae, or parasites. Different flow rates control different organisms. Therefore, a flow rate suitable for controlling bacteria or free-floating algae may not be effective against parasites. Larger organisms like parasites are more resistant to irradiation and require a slower flow rate to extend UV exposure time. To adjust UV exposure time, simply increase or reduce the rate water is flowing through the UV sterilizer.

More Info Via LiveAquaria

revhtree · Jul 13, 2012

How many of you use a UV Sterilizer?

Ace25 · Jul 13, 2012

I find them to be very harmful in a reef environment because they indiscriminately kill everything that passes through it, good bacteria, pods, etc. In a reef tank, diversity of life is a good thing, in a fish only tank, not so much. So I think they are acceptable to use in a fish only environment, but not acceptable to use in a reef environment.

wysiwyg · Jul 13, 2012

i use one and love it i have a mostly fish system with a few palys mushrooms and gsp and kenyas

CJO · Jul 13, 2012

Ace25 said:
I find them to be very harmful in a reef environment because they indiscriminately kill everything that passes through it, good bacteria, pods, etc. In a reef tank, diversity of life is a good thing, in a fish only tank, not so much. So I think they are acceptable to use in a fish only environment, but not acceptable to use in a reef environment.

I agree. The only time I would use one would be on a hospital tank for a fish or coral with a disease.

cJ

bct15 · Jul 13, 2012

Ace25 said:
I find them to be very harmful in a reef environment because they indiscriminately kill everything that passes through it, good bacteria, pods, etc. In a reef tank, diversity of life is a good thing, in a fish only tank, not so much. So I think they are acceptable to use in a fish only environment, but not acceptable to use in a reef environment.

I have to disagree here, I have a full blown mixed reef with sps, lps, and zoas. I run my uv sterilizer full time, never had an issue with any coral incompatibility with the skimmer, nitrates and phosphates are at a minimum, have billions of pods, keep great (expert only) fish alive, rarely see any unwanted algae (wipe glass once every other week), have crystal clear water with no sock, have had no ich problems (a couple fish have come in with it but it quickly goes away) and do not use a hospital or quarantine tank. Mine feeds into my skimmer and every tank I will own from this point on will have one, but to each his own. This was my first tank with one, and I personally have noticed a difference.

Steelerfan747 · Jul 13, 2012

I had one many years ago and it worked well but did not have one on my last tank since it ran with a fuge nor do I have one on my current tank.

Rockadile · Jul 13, 2012

I dont understand them myself. I mean you are putting a certain amount of water through this thing at one time which is then put back into the main tank. Wouldnt the treated water then become contaminated upon entering the tank? My reasoning tells me that unless all the water is put through one of these at one time you are not doing much of anything.

bct15 · Jul 13, 2012

Rockadile said:
I dont understand them myself. I mean you are putting a certain amount of water through this thing at one time which is then put back into the main tank. Wouldnt the treated water then become contaminated upon entering the tank? My reasoning tells me that unless all the water is put through one of these at one time you are not doing much of anything.

Mine feeds into my skimmer, then the water is skimmed of dead organics etc. same concept as passing the water through a carbon reactor, phosphate reactor, or any other device. You have a flow going through any filtration device, and the water is filtered then put back in the system. In this case, depending on the uv exposure time, the target organism is completely killed off in the water, the slower the flow rate the more that is killed. The water is not recontaminated because ALL of the targets are dead, unless someone gets zombie algae or ich going for fish brains. A high flow rate mostly targets algae, a lower flow rate targets parasites.

Rockadile · Jul 13, 2012

the sterile water would no longer be sterile once introduced back to the DT. That water would have the same contaiments it had prior to entering the UV. And that is my point. unless more water is going through the UV at one time then what is not, I do not see the good in it.

bct15 · Jul 13, 2012

Rockadile said:
the sterile water would no longer be sterile once introduced back to the DT. That water would have the same contaiments it had prior to entering the UV. And that is my point. unless more water is going through the UV at one time then what is not, I do not see the good in it.

The contaminants are dead, and in my case have been skimmed because my uv feeds into my skimmer like most people who use one...they are not going come back to life. UV sterilizers are very good at doing what they were designed to do, kill what passes through them...of the flow rate is right it has almost (if not) a 100% kill rate. You may be reintroducing the organisms body (because you are not vaporizing it), it is not the same as an RO, it is killing living organisms not removing dissolved solids such as bacteria, algae, and parasites. Once the water has passed through the UV the target organisms are not, I repeat are not, being reintroduced because...they are dead. Look at all major filtration systems, such as the drinking water system on an oil rig and you will see UV sterilizers...the organisms not being targeted Mather through but whatever the target organism is based on flow rate will not, this is a fact. You might need to google how UV sterilizers work and what try do so you have a better understanding because I tried explaining. If you want to remove dissolved solids use an RO before you add water, if you want to kill microorganisms use a UV, if you wan to remove phosphates use GFO etc. Nobody argues whether they kill the organisms, most people who do not use them is because they feel the UV kills things to well and remove even the beneficial organisms like everybody before me stated.

Rockadile · Jul 13, 2012

If pour ro water in tap water, that ro water is no longer ro. If I put sterile water into tank water it is no longer sterile . No you are not reintroducing the organisms back into your tank. the water is become reinfected.

bige · Jul 13, 2012

I think you can prove your point either way. Just like there are people who don't think skimmers do anything.

bct15 · Jul 13, 2012

Rockadile said:
If pour ro water in tap water, that ro water is no longer ro. If I put sterile water into tank water it is no longer sterile . No you are not reintroducing the organisms back into your tank. the water is become reinfected.

What are you saying here, the tank water has the organisms or water coming out of the UV. The overall total tank problem is a simple calculus rate of reduction problem. The water is not passed through the UV sterilizer once then reintroduced, it is constantly being sterilized. To simplify, the water that passes through the UV and is reintroduced, free of target organisms, reducing the concentration of target organisms. The then diluted total water is passed back through the UV further reducing the amount of target organisms. Eventually the amount of target organisms is reduced to an insignificant concentration. For my case, 3 times my tank volume is turned over an hour...the amount of dilution however is a function of the flow rate compared to the total volume of the system, which requires a properly sized UV sterilizer to eliminate the target organisms. The removal rate must be higher then the organism growth or reproduction rate.

Using your example, if I add a small amount of RO water to a constant volume of tap water, the tap water has been slightly diluted more towards pure water. If I then remove a small amount of this constant volume and pass it through the RO system then reintroduce it, the water is further reduced towards pure water. As I continue this cycle the water purity continues to approach pure water. After a certain amount of cycles have passed the water will have reached a saturation point (or limit) in which it can be considered pure or RO water.

The same concept applies to GFO, carbon, even a protein skimmer...

Rockadile · Jul 13, 2012

okay so now I get it.

Pappy · Jul 13, 2012

Ace25 said:
I find them to be very harmful in a reef environment because they indiscriminately kill everything that passes through it, good bacteria, pods, etc. In a reef tank, diversity of life is a good thing, in a fish only tank, not so much. So I think they are acceptable to use in a fish only environment, but not acceptable to use in a reef environment.

I disagree...good bacteria is all on the rocks and in the sand. And pods generally are there as well so the good stuff doesn't ever reach the sterilizer and if plumbed and separated in sumo from fuge I see this happening at a very minimal.

Mike D "like the beastie boys" Sent from my iPhone using Tapatalk

uall8up · Jul 13, 2012

I use one and will never stop!!! Best thing I ever did. All my little critters are as happy as a clam!!!

WesF · Jul 13, 2012

They are not harmful, because they do not perform as advertised. Placebo effect. I've seen some microbiological studies on the industrial level showing how ineffective they are. They no longer use them on the water systems at work (big pharma co.). Waste of money.

bct15 · Jul 13, 2012

WesF said:
They are not harmful, because they do not perform as advertised. Placebo effect. I've seen some microbiological studies on the industrial level showing how ineffective they are. They no longer use them on the water systems at work (big pharma co.). Waste of money.

After my dad was killed, my mom did not take care of his pond for over two years. The water ended up looking like pea soup, I bought and installed a UV sterilizer and only the UV sterilizer and the water was crystal clear three days later. Placebo may make my headache go away but it can't make the water turn clear..or change test results.

Do you have any of these studies for me to see, I'm assuming that the water is already heavily filtered at this pharmaceutical company and UV may not be necessary, or were presented by a filtration company trying to demonstrate how their product is far superior. There is plenty literature explaining the effects of UV radiation on various living organisms. It's not smoke and mirrors it's physics, infact I believe I have seen some people quoting some of this literature in a recent LED vs Metal Halide thread...