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Nolaboi

Aquarium Advice Regular
Joined
Jan 23, 2013
Messages
95
What do you guys think about a uv sterilizer on a freshwater tank? Is it a good choose
 
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I would drive by the LFS but don't stop, toss your money out the window and continue driving to save yourself some time since you've just wasted your money. They will serve no purpose in a freshwater aquarium unless your treating green water, otherwise they won't prevent algae or disease like some people suggest..save your pennies.
 
I would drive by the LFS but don't stop, toss your money out the window and continue driving to save yourself some time since you've just wasted your money. They will serve no purpose in a freshwater aquarium unless your treating green water, otherwise they won't prevent algae or disease like some people suggest..save your pennies.

Why do you say they don't work.?
 
Why do you say they don't work.?

Here a list of commons myths and facts people think uv lights, I put the ink at the bottom so you can read the entire page if your bored.


FACTS (& MYTHS) ABOUT UV STERILIZATION;

Here are few things UV Sterilization will NOT do:

[1] UV sterilization will not cure infected fish of bacterial or fungal diseases. A UV can aid in cure by killing bacterial pathogens in the water column and fungal spores, also by improvement of the Redox potential (which is much more important than many realize based on scientific research) and general water quality.

[2] A UV sterilizer will not kill ich trophozoites already on the fish (but then medications don't either), but UVC can again slow the spread of ich tomites in the water column (but usually not out right kill ich tomites). However by water quality improvement (such as Redox Potential) and lowering of pathogenic bacteria, the fish has more natural resistance to fight Marine Cryptocaryon or FW Ich.

[3] A UV sterilizer will not kill beneficial bacteria such aerobic bacteria, as this bacterium is effective when attached to a surface of high water flow such as the sponge of a sponge filter, not when in the water column. In fact relatively new scientific evidence shows nitrifying bacteria to be sticky and adheres to the surfaces like glue this is why the myth of UV Sterilizers killing beneficial bacteria is just that, a myth. It still may be best to turn off a Sterilizer unit when introducing bacteria in liquid form to seed a new aquarium.

[4] UV Sterilization will not remove or destroy algae growing on tank or pond sides, rocks, decorations, etc. However UV Sterilization can aid in the spread of certain algae that utilize spores as part of their mode of spread/replication.

Certain problem algae such as hair algae; most of the time hair algae comes attached to the plant that was purchased, or it may come in attached to the shells of snails or similar transferred rocks, etc. Unfortunately for this type of algae, you find little aid from a UV Sterilizer.
See: Aquarium or Pond Algae

[5] UV Sterilization will NOT kill off copepods and other small life forms in a Reef or Nano Reef Aquarium.
This is one of the more laughable myths about the use of UV Sterilizers in reef aquariums as these copepods live at or near the bottom of live rock piles (making a pile with small pieces is best for copepods), they are not active in the water column. If properly installed, the UV should have at least a fine pore sponge filter media as a pre-filter, which will further stop the “ingestion” of these and other minute life forms (the UV benefits as well by being more efficient).
What is interesting about this myth is that many who spread this misinformation use filters such as the Ocean Clear Micron Filters systems (which are excellent micron filters), these filters will filter out any copepods that get caught up in the water column and “sucked” into the filter. As well even “pods” that do manage to find their way into the UV Sterilizer are rarely killed due to size as the typical flow rate of 20+ gph is not low enough to kill them (you would need at least 10 gph per watt, which I do recommend running a UV Sterilizer at flow rate of under 10 gph per watt for this reason).

The bottom line here is that I have maintained MANY Reef aquariums with UVs with growing copepods, anemone and other creature populations. Honestly this is one of the worst urban myths in the aquarium hobby about UVs (mostly spread on the internet in misinformed forums which never conduct or read scientific evidence to back up these absurd statements). The only truth to these statements is that UV Sterilizers can destroy some microscopic food sources needed by some of these organisms (usually planktonic algae, although timers that turn the UV on during certain hours is an easy remedy for this possible problem).

For more on this myth/controversy, please see this article:
More UV Sterilizer Questions/Myths Answered

[6] UV Sterilization NOT remove minerals from aquarium water, however UVC Sterilization will also aid in the removal of oil based (carbon based) pollutants.

[7] The use of Ultraviolet Sterilizers will NOT lower fish immunity, in fact from my many controlled studies, the opposite is true. Although the exact mode is theoretical, evidence points towards improved Aquarium Redox being at least part of the reason.
See also this article: “Fish Immune System and UV Sterilization”

[8] UV Sterilization will NOT make up for poor aquarium maintenance practices such as over crowding, over feeding, inadequate filtration, poor cleaning practices, improper water parameters, and more.
This point is likely the cause for anecdotal statements that fish coming from tanks that had UV Sterilization, then are placed in a tank without an Ultraviolet Sterilizer resulting in “losses” may be dealing with (besides the above point of improved immunity, which will be lowered after transfer). Often an aquarist (I have also performed this as well for studies) will rely too much on the Sterilizer/Clarifier for water quality, clarity, etc., as a UV Sterilizer will often keep a tank clear and healthy in appearance even when correct water changes, mineralization, etc. are not performed. For this reason the fish may not be has healthy as they should since a Sterilizer should NEVER be relied on as a replacement for good aquarium maintenance practices. Along this same line of thought, often aquariums maintained this way will have low KH and falling pH which can result in osmotic shock and even death when transferred.

[9] UV Sterilization is only useful for water clarification; This myth is unfortunately perpetuated by the tidal wave of low cost UV Sterilizers from companies such as Submariner, Green Killing Machine and more.
What happens is users (often based on non-scientific reviews on Amazon or aquatic forums) will purchase these and find reasonable clarification results (even then not always), but find no improvement in Redox Balance, Fish, & overall aquarium health. These persons will then write about this anecdotal observation in forums, further reviews, Yahoo Answers, etc further perpetuating this myth.
Hopefully any reader has already figured out the lack of scientific truth to this myth after reading this far in this article.
See Also: Green Killing Machine, Submariner Review These are best for water clarification ONLY.

[10] UVC Light energy will not penetrate a plastic or pvc shell of a UV Sterilizer; even a clear or transparent plastic viewing window, hose barb or similar does not allow the passage of UVC light energy. All you are seeing is blue light.

Taken from AAP,

UV Sterilization, Aquarium & Pond; How To use UVC, Information

With good tank maintenance, a proper lighting schedule, and proper QT techniques in my opinion they're worthless. I've been breeding some of the rarest cichlids available for decades and I've never owned or have any intention to own one. I don't have algae, disease, or any other issues that warrart runnning one. If you feel the need to spend the money then that's your choice, but my opinion your better off spending the money on a more water conditioner and changing alot more water.
 
Last edited:
Here a list of commons myths and facts people think uv lights, I put the ink at the bottom so you can read the entire page if your bored.

FACTS (& MYTHS) ABOUT UV STERILIZATION;

Here are few things UV Sterilization will NOT do:

[1] UV sterilization will not cure infected fish of bacterial or fungal diseases. A UV can aid in cure by killing bacterial pathogens in the water column and fungal spores, also by improvement of the Redox potential (which is much more important than many realize based on scientific research) and general water quality.

[2] A UV sterilizer will not kill ich trophozoites already on the fish (but then medications don't either), but UVC can again slow the spread of ich tomites in the water column (but usually not out right kill ich tomites). However by water quality improvement (such as Redox Potential) and lowering of pathogenic bacteria, the fish has more natural resistance to fight Marine Cryptocaryon or FW Ich.

[3] A UV sterilizer will not kill beneficial bacteria such aerobic bacteria, as this bacterium is effective when attached to a surface of high water flow such as the sponge of a sponge filter, not when in the water column. In fact relatively new scientific evidence shows nitrifying bacteria to be sticky and adheres to the surfaces like glue this is why the myth of UV Sterilizers killing beneficial bacteria is just that, a myth. It still may be best to turn off a Sterilizer unit when introducing bacteria in liquid form to seed a new aquarium.

[4] UV Sterilization will not remove or destroy algae growing on tank or pond sides, rocks, decorations, etc. However UV Sterilization can aid in the spread of certain algae that utilize spores as part of their mode of spread/replication.

Certain problem algae such as hair algae; most of the time hair algae comes attached to the plant that was purchased, or it may come in attached to the shells of snails or similar transferred rocks, etc. Unfortunately for this type of algae, you find little aid from a UV Sterilizer.
See: Aquarium or Pond Algae

[5] UV Sterilization will NOT kill off copepods and other small life forms in a Reef or Nano Reef Aquarium.
This is one of the more laughable myths about the use of UV Sterilizers in reef aquariums as these copepods live at or near the bottom of live rock piles (making a pile with small pieces is best for copepods), they are not active in the water column. If properly installed, the UV should have at least a fine pore sponge filter media as a pre-filter, which will further stop the “ingestion” of these and other minute life forms (the UV benefits as well by being more efficient).
What is interesting about this myth is that many who spread this misinformation use filters such as the Ocean Clear Micron Filters systems (which are excellent micron filters), these filters will filter out any copepods that get caught up in the water column and “sucked” into the filter. As well even “pods” that do manage to find their way into the UV Sterilizer are rarely killed due to size as the typical flow rate of 20+ gph is not low enough to kill them (you would need at least 10 gph per watt, which I do recommend running a UV Sterilizer at flow rate of under 10 gph per watt for this reason).

The bottom line here is that I have maintained MANY Reef aquariums with UVs with growing copepods, anemone and other creature populations. Honestly this is one of the worst urban myths in the aquarium hobby about UVs (mostly spread on the internet in misinformed forums which never conduct or read scientific evidence to back up these absurd statements). The only truth to these statements is that UV Sterilizers can destroy some microscopic food sources needed by some of these organisms (usually planktonic algae, although timers that turn the UV on during certain hours is an easy remedy for this possible problem).

For more on this myth/controversy, please see this article:
More UV Sterilizer Questions/Myths Answered

[6] UV Sterilization NOT remove minerals from aquarium water, however UVC Sterilization will also aid in the removal of oil based (carbon based) pollutants.

[7] The use of Ultraviolet Sterilizers will NOT lower fish immunity, in fact from my many controlled studies, the opposite is true. Although the exact mode is theoretical, evidence points towards improved Aquarium Redox being at least part of the reason.
See also this article: “Fish Immune System and UV Sterilization”

[8] UV Sterilization will NOT make up for poor aquarium maintenance practices such as over crowding, over feeding, inadequate filtration, poor cleaning practices, improper water parameters, and more.
This point is likely the cause for anecdotal statements that fish coming from tanks that had UV Sterilization, then are placed in a tank without an Ultraviolet Sterilizer resulting in “losses” may be dealing with (besides the above point of improved immunity, which will be lowered after transfer). Often an aquarist (I have also performed this as well for studies) will rely too much on the Sterilizer/Clarifier for water quality, clarity, etc., as a UV Sterilizer will often keep a tank clear and healthy in appearance even when correct water changes, mineralization, etc. are not performed. For this reason the fish may not be has healthy as they should since a Sterilizer should NEVER be relied on as a replacement for good aquarium maintenance practices. Along this same line of thought, often aquariums maintained this way will have low KH and falling pH which can result in osmotic shock and even death when transferred.

[9] UV Sterilization is only useful for water clarification; This myth is unfortunately perpetuated by the tidal wave of low cost UV Sterilizers from companies such as Submariner, Green Killing Machine and more.
What happens is users (often based on non-scientific reviews on Amazon or aquatic forums) will purchase these and find reasonable clarification results (even then not always), but find no improvement in Redox Balance, Fish, & overall aquarium health. These persons will then write about this anecdotal observation in forums, further reviews, Yahoo Answers, etc further perpetuating this myth.
Hopefully any reader has already figured out the lack of scientific truth to this myth after reading this far in this article.
See Also: Green Killing Machine, Submariner Review These are best for water clarification ONLY.

[10] UVC Light energy will not penetrate a plastic or pvc shell of a UV Sterilizer; even a clear or transparent plastic viewing window, hose barb or similar does not allow the passage of UVC light energy. All you are seeing is blue light.

Take from AAP,

UV Sterilization, Aquarium & Pond; How To use UVC, Information

With good tank maintenance, a proper lighting schedule, and proper QT techniques in my opinion they're worthless. I've been breeding some of the rarest cichlids available for decades and I've never owned or have any intention to own one. I don't have algae, disease, or any other issues that warrart runnning one. If you feel the need to spend the money then that's your choice, but my opinion your better off spending the money on a more water conditioner and changing alot more water.

Now that's what I call info thank you so much for the time you put in writing that
 
Hukit, I respectfully disagree lol

I've had green water and nothing I did cleared it up. So I bought a green killing machine uv from petsmart and I consider it the best money spent. It cleared up in hours what I had been fighting for weeks. My only regret is that I didn't buy it sooner.

That said, I ran it for a couple of weeks and it's been unplugged since. Once my green water was gone I didn't see any reason to use it.

So I guess it depends on why you were thinking about buying one.
 
They will serve no purpose in a freshwater aquarium unless your treating green water.

I've had green water and nothing I did cleared it up. So I bought a green killing machine uv from petsmart and I consider it the best money spent. It cleared up in hours what I had been fighting for weeks.

I think you missed my first post, that's the only reason I stated I'd even try one. Although that would be my last resort as I'd try other methods to alleviate the problem prior to turning to a uv light.
 
I think you missed my first post, that's the only reason I stated I'd even try one. Although that would be my last resort as I'd try other methods to alleviate the problem prior to turning to a uv light.

I agree with all the info that that was given. It was a great read thanks Hukit. It makes explaining uv lights quite well. There is a ton of miss leading info about them and the only thing it does for me that I notice is clear the water. But I have some pretty nasty well water that's a pain to clear up and carbon was getting a little expensive, I don't even think it cleared the water this well.
 
I agree with all the info that that was given. It was a great read thanks Hukit. It makes explaining uv lights quite well. There is a ton of miss leading info about them and the only thing it does for me that I notice is clear the water. But I have some pretty nasty well water that's a pain to clear up and carbon was getting a little expensive, I don't even think it cleared the water this well.

Well my water is clear but I may want it a little more clear so I may want to add one just for the clear water lol
 
Well my water is clear but I may want it a little more clear so I may want to add one just for the clear water lol

It's not a magic bullet when it comes to water clarity, for simply polishing the water I'd recommend filter floss and Purigen.
 
I think you missed my first post, that's the only reason I stated I'd even try one. Although that would be my last resort as I'd try other methods to alleviate the problem prior to turning to a uv light.

I'm sorry Hukit, I did misread. :-D
 
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