UV Sterilizers

[florida joe]

The use of UV sterilizers in the aquarium has benefits if properly installed and maintained with really no downsides. UV light acts by damaging the DNA within living organisms so they cannot reproduce. How ever bacteria have repair enzymes that can repair the damage caused by UV light. This is one of the reasons a UV sterilizer is not 100% effective in eliminating bacteria. It can offer some help in the control of water borne pathogens, but it can not be relied on to guarantee that disease problems wont occur Spotte and Adams (1981) the reason for this is that the pathogens continue to reproduce with in the aquarium. Even if the UV sterilizer achieves a 100% kill rate, it is limited by the rate of flow through the UV sterilizer. And in a conventional closed system with recalculating water such as we have the pathogens never reach zero. They may hold these pathogens at bay but they do not eliminate them all together.
If you want to use a UV sterilizer some things to consider are wattage, flow rate, turbidity, temperature (most uv bulbs work best at 110 degress F so heat is a factor) of the water as well as target organism e.g. bacteria, viruses, ciliates. It should be mounted at the very end of filtration so it receives the cleanest clearest water possible. Installed where it can be isolated and removed for maintenance easily. The UV bulbs lose their intensity quickly dropping output by as much as 40 percent with in six months the sleeves encasing the bulb need to be scrupulously cleaned. Also the thickness of the water passing around the bulb factors into the kill ratio
Are they useful, definitely all-major aquariums are employing them? Are they for the home aquarist? IMO your money is best-spent on other things

 

[beth]

No guarantees on treating fish diseases with UV, and, it should really only be used in FO tanks. In FOWLR, and especially in reef tanks, the UV's indiscriminate zap on all kinds of bacteria interrupts the natural biofilter which you are trying to create by using LR and setting up a reef.

 

[florida joe]

Actually Beth in an established reef tank the old argument was that the UV destroyed plankton. But that argument fell apart when it is noted that plankton in a reef tank are both destroyed and produced by the aquarium’s inhabitants (Delbeek and Sprung) 2005.Again it is in an established reef tank that no down side to UV is indicated

 

[bgbdwlf2500]

Originally Posted by Beth
http:///forum/post/2622159
No guarantees on treating fish diseases with UV, and, it should really only be used in FO tanks. In FOWLR, and especially in reef tanks, the UV's indiscriminate zap on all kinds of bacteria interrupts the natural biofilter which you are trying to create by using LR and setting up a reef.

its my understanding that the "good" bacteria are not free floating, they stick to the rocks, substrate etc... so they should never pass through the UV

 

[beth]

Actually, bacteria which is a source of food for filter feeders and micro organisms, are greatly diminished by the use of UV in a reef tank. The bacteria is in the water column and easily passes through to the UV bulb. UV's purpose is to kill bacteria, and other things, and it does. In a reef tank, you certainly don't want your bacterial colonies, upon which many filter feeders rely upon for sustenance, to be diminished. Thus, don't use a UV in a reef tank or a tank with LR. I'm sure some will disagree, but

. I am a firm believer in natural filters (such as filter feeders, live rock, live sand, sand beds, etc.) and less in favor of mechanical devises such as UVs, canister filters, sponge filters, carbon, etc. as a means of maintaining marine tanks. A matter of opinion and preference.

 

[sepulatian]

Originally Posted by bgbdwlf2500
http:///forum/post/2623206
its my understanding that the "good" bacteria are not free floating, they stick to the rocks, substrate etc... so they should never pass through the UV
Biological bacteria colonizes on surfaces. That is not all of the micro fauna, micro bacteria, and other microscopic organisms that are "good" in the tank though.

 

[racin24fan]

So if someone were to buy one what would be the recommendation for the best and most cost effecient one to buy?

 

[natclanwy]

Joe, Have to agree with Beth on this one. I think UV filters have their place LFS stock tanks, QT, and fish only tanks, but not in a reef tank they kill too many things that are benificial to our tanks along with the bad.

 

[florida joe]

people this was my last statment on my thread
Are they useful, definitely all-major aquariums are employing them? Are they for the home aquarist? IMO your money is best-spent on other things

 

[tizzo]

Starting from the basics, as I read what you wrote Joe, I am asking (again, sincerely asking, not trying to make a point or start a debate) but you wrote, "It can help control some water borne pathogens" and I think I read on the UV box that it's made for killing free floating algae.
But really, what good are they? I mean, some people swear by them, why? If they do not irradicate the pathogens, and that algae is a good thing IMO, keeps me from adding DT's.
What is a good solid argument in favor of them?

I don't have a UV. I don't want one. Matter of fact I just traded the 36 watter that came with my tank, for a frogspawn. BUt the people who do have them, swear by em. Why?

 

[beth]

There is no good argument for using them for the home aquarist. Most hobbyist want a UV to control fish diseases, not remove algae. Most hobbyists want to substitute a $200 UV for a >$100 QT set up. Why? I still ponder this after so many years. There is something about setting up a QT that seems so daunting for many hobbyists.

 

[florida joe]

Originally Posted by Beth
http:///forum/post/2625564
There is no good argument for using them for the home aquarist. Most hobbyist want a UV to control fish diseases, not remove algae. Most hobbyists want to substitute a $200 UV for a >$100 QT set up. Why? I still ponder this after so many years. There is something about setting up a QT that seems so daunting for many hobbyists.
Beth I totally agree again as stated in my thread that they are best used in professional exhibits.

 

[florida joe]

Originally Posted by Tizzo
http:///forum/post/2625353
Starting from the basics, as I read what you wrote Joe, I am asking (again, sincerely asking, not trying to make a point or start a debate) but you wrote, "It can help control some water borne pathogens" and I think I read on the UV box that it's made for killing free floating algae.
But really, what good are they? I mean, some people swear by them, why? If they do not irradicate the pathogens, and that algae is a good thing IMO, keeps me from adding DT's.
What is a good solid argument in favor of them?

I don't have a UV. I don't want one. Matter of fact I just traded the 36 watter that came with my tank, for a frogspawn. BUt the people who do have them, swear by em. Why?
Every time I try to get out they keep pulling me back in

ok my friend let me see if I can come up with a positive for UV.
Lets see what microorganisms UV kills.
Staphylococcus aurous
E coli
Mycobacterium tuberculosis
Salmonella SP
Chlorella vugaris
Nematode (eggs)
Trichodina nigra (protozoan)
Paramecium (protozoan)
Ichthyophthirius SP, (ICK)
A definite list of nasty IMO
In nature, UV light continuously bombards the oceans surface braking down larger organic molecules into smaller ones. In our closed systems with a high animal load, dissolved organic nitrogen and dissolved organic carbon levels are often several times that of the ocean. A study by Ishi and McGlathery (2003) found that calculated dissolved organic carbon levels dropped by 17% after 36 hours exposure to UV.
It has also recently been shown that in the reef aquaria, bacteria levels can also be several times higher then on a coral reed (Harker 2001). Again UV light may prove useful in lowering these levels.Since one of our major goals is to mimic natural coral reefs when we set up a closed environment
Once again I must explain my thread was not an endorsement for UV as I stated the home aquarist is better off using his money elsewhere. BUT it does have its place in reef keeping. On the professional exhibit stage

 

[tizzo]

Originally Posted by florida joe
http:///forum/post/2625729
Every time I try to get out they keep pulling me back in

ok my friend let me see if I can come up with a positive for UV....
Once again I must explain my thread was not an endorsement for UV as I stated the home aquarist is better off using his money elsewhere.
I realize you were not endorsing it. But I like to know the pros and cons just incase someone ever asks.
For example, a friend of mine was all upset cause they just spent a ton of money on a skimmer, then had another hobbiest tell them they didn't need it so they asked me. Knowing both sides of the "argument" I was able to 'educate' them to make their own decision, and add my own bias as to having one.

 

[florida joe]

Originally Posted by Tizzo
http:///forum/post/2626869
I realize you were not endorsing it. But I like to know the pros and cons just incase someone ever asks.
For example, a friend of mine was all upset cause they just spent a ton of money on a skimmer, then had another hobbiest tell them they didn't need it so they asked me. Knowing both sides of the "argument" I was able to 'educate' them to make their own decision, and add my own bias as to having one.

Well my friend I am sure you know all to well there be pros and cons to almost every aspect of this hobby of ours. I am starting to think (now that’s a novel approach for me) that there are so many variables in each individuals set up that one almost has to try things for them self of course the down side to that is the cost factor