Is a UV necessary??

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evojoey

Fire Eel
MFK Member
Jul 31, 2008
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Turnersville, South Jersey
I keep seeing people with UV lights on filters and such. I have one on my koi pond but that is to control the pea soup that happens in the summer. What is the advantage, if their is any, of a UV on an indoor fishtank?
 
From my understanding although I may be wrong...People put UV sterilizers on larger indoor tanks becuase the light kills illness causing bacteria...

I have a 225, its been up for around 3 years, I've never had a UV sterilizer and Ive never had a outbreak of anything. So idk if they are usefull or not.
 
This is all my personal opinion....To stop the "pea soup" I would add extra plant cover to block the sun from causing pea soup. In home aquariums, it kills all diseases when the bulb is replaced as much as it should be. BUT I think it lowers a fish's immune system. Never getting sick causes the body to because less capable of ridding itself of disease. When/if a fish does get sick they are more likely to succumb. I prevent disease in my tanks with proper husbandry. Like Qt'ing a fish for no less than 9 weeks in my hospitals, before adding them to a population. I also change water no matter what. Even if my nitrates are below 15 I still change water...I do get diseases, but I medicate and it gets better, and/or goes away...I hope this helps.
 
good point about lowering the immune system, this would make sence though it probably differs from fish to fish
 
bigspizz;2243175; said:
This is all my personal opinion....To stop the "pea soup" I would add extra plant cover to block the sun from causing pea soup. In home aquariums, it kills all diseases when the bulb is replaced as much as it should be. BUT I think it lowers a fish's immune system. Never getting sick causes the body to because less capable of ridding itself of disease. When/if a fish does get sick they are more likely to succumb. I prevent disease in my tanks with proper husbandry. Like Qt'ing a fish for no less than 9 weeks in my hospitals, before adding them to a population. I also change water no matter what. Even if my nitrates are below 15 I still change water...I do get diseases, but I medicate and it gets better, and/or goes away...I hope this helps.

Makes complete sense. I do find that water lillies and hyacinths help out a great deal with green water in my pond. The light is there for the beginning and end of the season when the plants are not established. I'd say that my UV is on no longer that 4 weeks total, from the end of march to the end of october.
As far as my tank inside, as long as I keep up my normal cleaning routine of 75 gal. water changes once a week, I should never need a UV for the tank. Correct?
 
I got my first UV light 5 years ago and have been using them on some (but not all) of my tanks ever since…

I’ve heard the theory that using a UV light will weaken the immune system for years… and I’ve seen a TON of evidence in my own tanks that this is 100% false…

Here’s my experience I base this on…

I’ve bought several large groups of Blue Dempseys to be raised in search of “superior” quality fish to be used as breeders. As I know they are susceptible to parasitic infections I’ve raised them in tanks with UV lights…

Once I choose a fish to be a breeder I move it into tanks without UV lights and begin breeding. Thus far I’ve moved over a dozen Blue Dempseys out of UV tanks and into non UV tanks. Not once have I lost one to any form of illness (only aggression).

I should also add that while the others I was communicating with about Blue Dempseys were constantly fighting white stingy poop and other symptoms of parasitic infections, I have not lost one Blue Dempsey to parasitic infection while raising them in tanks with UV lights and I have not once used any medications to prevent or treat parasites.

Is a UV light necessary?

Not at all…

What is the advantage, if there is any, of a UV on an indoor fishtank?

If used properly, they will destroy any living entity that passes through the light including but not limited to bacteria, fungus, parasites & algae…
They turn clean clear water into crystal clear water. If I understand correctly, they force tiny particles that pass through the UV light to cling together allowing the mechanical filtration to remove these, now larger, particles. This may not be correct, but after 5 years of use I can personally attest that my UV tanks are crystal clear, where my non UV tanks are only clean & clear.
 
I agree with nc_nutcase completely. In addition, the UV ozonizes the water creating a better water quality for the aquarium. I have 4 tanks running, 2 with and 2 without UV sterilizers. All are clean, but the UV sterlized water is more clear. I recommend them.
 
I've had worse luck with UV than without. I quit using it for the immunity issues previously mentioned. It may not be true, but it's not worth risking it when I've had a lot less trouble without it.
 
I also agree with all said, but to even think top water quality is not attainable, without UV, is just not the case...I will never use one. To me, it is just excess hobby cost, that is 100% avoidable with added manual effort...




EDIT: I was ninja'd...hahaha
 
rallysman;2245589; said:
I've had worse luck with UV than without. I quit using it for the immunity issues previously mentioned. It may not be true, but it's not worth risking it when I've had a lot less trouble without it.


Could you explain your experience a little so we might hav an idea of what didn't work for you?
 
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