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Organic Farmer
07-18-2005, 01:14 PM
i plan on hooking up a uv sterilezer to prevent disease-causing micro-organisms has anybody used them in the past? are they worth while?and do i have to worry about making any future breeders sterle that is in fertile?even if i were to only run it a few hours a week? thank you

Kagan
07-21-2005, 06:32 PM
Hi,

I have used UV for the last 4 years now. I did not see it as a must have but it is very usable if used on the output of the water tank. You will have a rather "sterile" water for water changes.. For regular usage, I dont think that it is effective unless you have a planted tank. Of course my recommendation is to use it time to time not continuously.

Kagan

Organic Farmer
07-22-2005, 12:22 PM
thank you for your time ill give it a shot and let you know how it goes

Cosmo
07-23-2005, 09:02 PM
mine run for about 20 hours a day, 365 days a year (sometimes 366 :D )

No ill effects

Jim

Organic Farmer
07-24-2005, 09:39 AM
thanks for your reply jim i think ill only use it 20 or 30 hours a week if i rember correctly the last time i used one it has a tendencey to "buff " the water

Dave C
07-24-2005, 09:59 AM
Why bother to use one (or buy one) at all for 20-30 hours a week? That regime makes sense if you're trying to remove free-floating algae but that's about it. I suggest you either ignore the unproven claims that UV weakens the immune system of the fish or pass on the unit. I used a sterilizer for a few years and found it wasn't worth the cost. If you buying quality, healthy stock... quarantine all new arrivals... maintain good water quality with water changes and not overfeeding... you don't need a sterilizer.

john2gs
07-27-2005, 06:23 PM
I use a jebo 13 watt UVC unit that is on 24/7.

I also disagree that the fish's immune system will be weaken because of the usage of UVC.

Even if the UVC is used.....it will not entirely kill all the bacteria/parasites/pathogens/etc in your tank set-up. There will still be some who will live. Remember, that only pathogens that passes thru the UVC are killed. Those that are still free floating in your tank...still multiplies by the minute......so even if you use your UVC....the other pathogens still multiply. Therefore, not every pathogen is killed.

The use of UVC is to lessen the numbers of pathogens..or prevent bacterial/pathogen break out........but NOT COMPLETELY destroy all the numbers.

some turn it on for only a few hours.....some turn it on 24/7. I believe, you are just defeating the purpose of the UVC if you only turn it on for a few hours...since the #s of pathogens will multiply back....once you turn it off. I turn it on 24/7...to keep the #s down.


Those limited # of pathogens/bacteria/etc......will still keep the immune system of your fish high....and not weaken them....

some believes in UVC..some dont........I guess Im one of those who believe in it :)


just my 2 cents....

korbi_doc
07-28-2005, 09:09 AM
:D Soooo controversial, there will probably never be agreement on this one! I do agree with Dave that the way we maintain our tanks, with good quality healthy stock, there is no real necessity for UV. That being said, I do use it on some tanks 24/7, seems to help with algea control & there may be some protection against outbreaks of problems. There is absolutely no "sterilization" per se, since there is, as John stated, only effects upon the water being passed thru the UV transiently, & that's why it should be pumped thru slowly, to get the best effects. It is a very miniscule percentage of the total water volume in a tank with live organisms, fish & bacteria, (other pathogens & parasites included). We only hope that it helps to control a pathogen outbreak, but in & as of itself, it cannot do any better than that, it is no panacea. Perhaps it would be best put to use in QT tanks with new fish being prepared to be introduced into our stock, (other than algae control.) just a few thoughts, Dottie :sun:

john2gs
07-28-2005, 11:26 PM
:D Soooo controversial, there will probably never be agreement on this one! I do agree with Dave that the way we maintain our tanks, with good quality healthy stock, there is no real necessity for UV. That being said, I do use it on some tanks 24/7, seems to help with algea control & there may be some protection against outbreaks of problems. There is absolutely no "sterilization" per se, since there is, as John stated, only effects upon the water being passed thru the UV transiently, & that's why it should be pumped thru slowly, to get the best effects. It is a very miniscule percentage of the total water volume in a tank with live organisms, fish & bacteria, (other pathogens & parasites included). We only hope that it helps to control a pathogen outbreak, but in & as of itself, it cannot do any better than that, it is no panacea. Perhaps it would be best put to use in QT tanks with new fish being prepared to be introduced into our stock, (other than algae control.) just a few thoughts, Dottie :sun:

I truly agree with what you said Dottie....

I actually use my UVC...24/7......just to keep the water crystal clear, lessen algae growth, and again....control and hoping to prevent any bacterial/pathogenic outbreak....

Dave C
07-29-2005, 07:36 PM
From what I have read you shouldn't expect much more then algae control from a 13w UV on a 125g tank. Either you would need way too much flow for that size bulb, or your flow would be so low as to barely turn over the tank contents. I highly recommend the book by Escobal on Aquatic Systems Engineering.

Cosmo
07-29-2005, 09:18 PM
Harleyguy... haven't noticed any change in water parameters from the UV.. Dotties right though.. very controversial subject lol.. I use mine to control algea, and, for just in case something's in the tank that needs to be killed...

According to most mfg's suggestions I've read, a 13 should be ok for a 125, trick is to match the pump flow to the light to get max killing during each pass thru..

Jim

john2gs
07-29-2005, 10:12 PM
UV bulb ===== maximum flow rate to control =====aquarium size
____________bacteria & algae == ==parasites
8w---------------120 gph------------n/a -------------under 75gal
15w--------------230 gph-----------75 gph -----------75 gal
18w--------------300 gph-----------100 gph ----------100 gal
25w--------------475 gph-----------150 gph ----------150 gal
30w--------------525 gph-----------175 gph ----------175 gal
40w--------------940 gph -----------300 gph----------300 gal
65w--------------1700 gph---------- 570 gph ---------570 gal
80w--------------1885 gph-----------625 gph ---------626 gal
120w-------------3200 gph-----------900 gph ---------900 gal
130w-------------3400 gph----------1140 gph --------1140 gal


some brands will recommend this:
7 watt UVC is good for 40-75 gallon tank
9 watt = 45-150 gallon tank
13 watt = 75-200 gallon tank

but again, it really depends on the UVC's company's recommendation....so better follow it.

Dave C
07-29-2005, 10:34 PM
The specific manufacturer should have nothing to do with the ability of a 13w bulb of killing pathogens. It's not mfr specific... 13w is 13w. But I don't want to argue with you. If you're interested, check out the book I suggested. It will list the dosage required to kill an entire list of bugs. But you may be disappointed. They only go as low as 25w for their calculations, anything less then that is considered unsuitable for most tanks, let alone 125g tanks.

But here's a link that summarizes much of the sterilizer discussion in that book.

http://aquariumadvice.com/showquestion.php?faq=2&fldAuto=39&page=1

The premise that Escobal uses is that in order to kill most of the bugs in your tank you should turnover the contents of your tank twice a day. So you can figure out what flow rate will do that on your tank. For a 125g tank you will turnover 99.99% of your tank in 10.45 hours at a flow rate of 110gph. So that's roughly twice a day. To be effective he gives a maximum flowrate for different sized UV bulbs in a 2" housing. A 30w bulb can handle at most 125gph. Anything beyond that and your dwell time drops and the zap dosage is less then required to kill the bugs. So it would make sense that a 30w bulb would be optimal for a 125g tank.

What most people do though is just hook up any sized pump or filter to their UV and let it rip. What is the gph going through your sterilizer? If it's a lot more then 50-60gph then you're pretty much bypassing the sterilizer capabilities altogether. And if it is around 50gph then you are only turning over the tank contents once per day rather then twice so the growth in pathogens can render your sterilizer less the optimal.

john2gs
07-29-2005, 10:43 PM
The specific manufacturer should have nothing to do with the ability of a 13w bulb of killing pathogens. It's not mfr specific... 13w is 13w. But I don't want to argue with you. If you're interested, check out the book I suggested. It will list the dosage required to kill an entire list of bugs. But you may be disappointed. They only go as low as 25w for their calculations, anything less then that is considered unsuitable for most tanks, let alone 125g tanks.

But here's a link that summarizes much of the sterilizer discussion in that book.

http://aquariumadvice.com/showquestion.php?faq=2&fldAuto=39&page=1

The premise that Escobal uses is that in order to kill most of the bugs in your tank you should turnover the contents of your tank twice a day. So you can figure out what flow rate will do that on your tank. For a 125g tank you will turnover 99.99% of your tank in 10.45 hours at a flow rate of 110gph. So that's roughly twice a day. To be effective he gives a maximum flowrate for different sized UV bulbs in a 2" housing. A 30w bulb can handle at most 125gph. Anything beyond that and your dwell time drops and the zap dosage is less then required to kill the bugs. So it would make sense that a 30w bulb would be optimal for a 125g tank.

What most people do though is just hook up any sized pump or filter to their UV and let it rip. What is the gph going through your sterilizer? If it's a lot more then 50-60gph then you're pretty much bypassing the sterilizer capabilities altogether. And if it is around 50gph then you are only turning over the tank contents once per day rather then twice so the growth in pathogens can render your sterilizer less the optimal.

hehehe......no need to argue bro. We are here to help each other :)

before selecting a UV sterilizer, determine your primary objective - whether to help control free floating algae or to control parasites. By doing so, you will be able to select the proper unit to achieve your intended goal.

UV sterilizers work on the principle that special flourescent UV lamps at a peak wavelength of approximately 254 nanometers, can effectively irradiate microorganisms in aquarium water when exposed to this light. UV light in this wavelength alters the genetic material in the organism's nucleus, shortening its normal life cycle. However, the application and the efficiency of a unit are determined by flow rate as well as the wattage and age of bulb.

Adjusting the flow rate through your UV sterilizer, that is, shortening the time organisms are exposed to the UV lamp (dwell time), alters its use. For example, controlling bacteria and free-floating algae can be accomplised w/ a relatively lower wattage unit as a higher flow rate. However, parasites are larger and more resistant to irradiation and require a longer dwell time to be affected by the UV light. A slower flow rate prolongs dwell time to expose parasites to an effective dose of UV light

thanks for the link. Very educational!

Dave C
07-29-2005, 11:04 PM
You got it. Though I don't know why a slow flow through a sterilzer won't kill parasites, bacteria & algae. It's worked well for me. So I don't see why you'd need two units. But what you've just posted is what I meant when I said "from what I have read you shouldn't expect much more then algae control from a 13w UV on a 125g tank".

p.s. if you liked that link you should get the book. Very informative. Here's a link

http://www.amazon.com/exec/obidos/tg/detail/-/1888381051/qid=1122695977/sr=1-1/ref=sr_1_1/103-7598505-3815056?v=glance&s=books

john2gs
07-29-2005, 11:24 PM
You got it. Though I don't know why a slow flow through a sterilzer won't kill parasites, bacteria & algae. It's worked well for me. So I don't see why you'd need two units. But what you've just posted is what I meant when I said "from what I have read you shouldn't expect much more then algae control from a 13w UV on a 125g tank".

p.s. if you liked that link you should get the book. Very informative. Here's a link

http://www.amazon.com/exec/obidos/tg/detail/-/1888381051/qid=1122695977/sr=1-1/ref=sr_1_1/103-7598505-3815056?v=glance&s=books

yes bro.........slow flow rate setting....especially with a high watt UVC..will be able to kill parasites, bacteria, and algae. With my previous post...i was just mentioning that...........killing bacteria and algae...the maximum flow rate that is effective is ALOT higher compared to the maximum flow rate to kill parasites to be effective.

In a 125 gallon tank.......using 13 watt UV........if you set the flow rate in a medium pace (for example 100 gph) ......it will be able to definitely zap both algae and bacteria. And since parasites are larger and more resistant to irradiation.........the flow rate SHOULD DEFINITELY BE ALOT SLOWER (for example.... 50 gph) to be killed.

In short, if your UV w/ a certain flow rate.......can kill algae, chances of killing bacteria is high too. But killing parasites may not occur.....since they require longer dwelling time.

If your UV w/ a certain flow rate....can kill parasites........definitely, the free floating algae, as well as the bacteria....should also be killed.


GRRRrrrrrRrrrrr, I hope you get my drift. Im sorry...Sometimes.....I cant express..what I wanted to say properly.....and makes things very confusing for people reading what Im saying....hehehehe

Anyways, again..thanks for the link! :)

Dave C
07-30-2005, 07:57 AM
I'm curious. What specific bacteria is it that you believe you're killing with the higher rate? And what specific parasites are being left behind? There's a list in that book that shows the required zap dosage for many, many types including algae. Given that list you are able to determined an appropriate gph & wattage to deliver the required UV for ample time. What are you basing your statements on? What is the gph you push through your UV and how are you measuring that gph?

john2gs
07-30-2005, 08:25 AM
I'm curious. What specific bacteria is it that you believe you're killing with the higher rate? And what specific parasites are being left behind? There's a list in that book that shows the required zap dosage for many, many types including algae. Given that list you are able to determined an appropriate gph & wattage to deliver the required UV for ample time. What are you basing your statements on? What is the gph you push through your UV and how are you measuring that gph?


Bro, I just read articles from dr foster and smith.

No specific bacteria or parasites mentioned on the articles. Very very general statements. Again, I will mention that......parasites are larger in size and more resistant to irradiation compared to bacteria and free floating algae. They need a longer dwelling/exposure w/ UV light.....compared to bacteria and free floating algae.

Thats why I stated in my previous post that "In short, if your UV w/ a certain flow rate.......can kill algae, chances of killing bacteria is high too. But killing parasites may not occur.....since they require longer dwelling time.

If your UV w/ a certain flow rate....can kill parasites........definitely, the free floating algae, as well as the bacteria....should also be killed."




about the gph...you will be able to measure it.....by your powerhead's or your canister's output power which is also in gph.

Dave C
07-30-2005, 08:55 AM
I heard you the first few times. But just saying that uv that can kill algae will kill bacteria is anecdotal at best. I wondered what bacteria you thought you were killing and what parasites you figured you were missing. It's ok, I think you've told me what I wanted to know.

And I understand how you can measure gph. I was just wondering what your output was. It's harder to measure on a filter as the flow changes from when the filter is clean to when it is dirty. The output from the mfr is when the filter is completely empty, no media at all. So it's overstated.

From what I've seen in the fishrooms I've been in and from descriptions & pics of others, most people just hook up their UV to a return pump on their wet/dry or the end of their Fluval and assume that they've taken care of the issue. In many cases they have completely circumvented the effectiveness of a sterilizer by blasting water through it at such a high rate that it does nothing. This may not be relevant to you, but this thread is being read by others besides you & I.

john2gs
07-30-2005, 09:05 AM
I heard you the first few times. But just saying that uv that can kill algae will kill bacteria is anecdotal at best. I wondered what bacteria you thought you were killing and what parasites you figured you were missing. It's ok, I think you've told me what I wanted to know.

And I understand how you can measure gph. I was just wondering what your output was. It's harder to measure on a filter as the flow changes from when the filter is clean to when it is dirty. The output from the mfr is when the filter is completely empty, no media at all. So it's overstated.

From what I've seen in the fishrooms I've been in and from descriptions & pics of others, most people just hook up their UV to a return pump on their wet/dry or the end of their Fluval and assume that they've taken care of the issue. In many cases they have completely circumvented the effectiveness of a sterilizer by blasting water through it at such a high rate that it does nothing. This may not be relevant to you, but this thread is being read by others besides you & I.

well....its not also safe to say that........w/ a 13 watt UVC in a 125 gallon tank, ONLY free floating algae is killed (as what you previously stated). I dont believe that at all.........i guess anecdotal too

You are right about stating that most Mfgs overstate the gph. Thats why with my canister which for example pumps 270 gph.......I know that water that passes thru the UVC will be less, but atleast I have a rough idea on what the gph will be...

and again you are right.....too high of gph, is not a good thing...since exposure is too fast.....which will not be effective at all.

Dave C
07-30-2005, 11:05 AM
Actually, what I said was "from what I have read you shouldn't expect much more then algae control from a 13w UV on a 125g tank". After rereading the link I gave, I would like to adjust that and say that it might not be very effective at algae control either. And that's not based on anecdotal evidence.

If you read the first link I gave it says "sterilizers less than 25 watts are not practical for tanks above 20 gallons." It is also amost solely discussing the elimination of bacteria and algae, hardly concerns itself with parasites. For instance "Streptococcus bacteria needs a zap dose of approximately 9000, algae needs about 22,000" and "one can see that improper sizing or flow will reduce the effectiveness of a UV sterilizer to unacceptable parameters – the bacteria will come out the other side unharmed."

To effectively eliminate algae & bacteria the author has chosen 30,000 for a minimum zap dose, which is delivered at 125gph for a 30w bulb. Your filter is probably averaging closer to 175gph on a 13w bulb and producing a zap dose of less then 4,000, which is why I say it may not be effective at algae control (required dose is 22,000) or even Streptococcus bacteria (which requires 9000 and is on the low end of bacteria).

The moral of the story is to buy the biggest unit you can afford for your tank and run it less then 24/7 at the optimum gph to turnover your tank contents 2x a day. On a 125g tank you could run it 24/7 at 100gph using a 30w unit and have optimal conditions for killing algae & most bacteria. Or you could get a 64w unit, run it at 275gph for 8.5 hours a day and achieve the same effect. The cost of the 30w unit is $100 or $200 less then a 64w unit. But the bulbs are almost the same price, say $50. And you will use the 30w bulb up 3x faster then the 64w bulb. So since you should replace the bulb every 6 months you will be replacing 3 of the 30w bulbs every 1.5 years and only replacing 1 of the 64w bulbs every 1.5 years. So the 64w unit will pay for the difference in initial cost in about a year and a half. After that the 64w unit is saving you cash over the 30w.

john2gs
07-30-2005, 11:34 AM
Actually, what I said was "from what I have read you shouldn't expect much more then algae control from a 13w UV on a 125g tank". After rereading the link I gave, I would like to adjust that and say that it might not be very effective at algae control either. And that's not based on anecdotal evidence.

If you read the first link I gave it says "sterilizers less than 25 watts are not practical for tanks above 20 gallons." It is also amost solely discussing the elimination of bacteria and algae, hardly concerns itself with parasites. For instance "Streptococcus bacteria needs a zap dose of approximately 9000, algae needs about 22,000" and "one can see that improper sizing or flow will reduce the effectiveness of a UV sterilizer to unacceptable parameters – the bacteria will come out the other side unharmed."

To effectively eliminate algae & bacteria the author has chosen 30,000 for a minimum zap dose, which is delivered at 125gph for a 30w bulb. Your filter is probably averaging closer to 175gph on a 13w bulb and producing a zap dose of less then 4,000, which is why I say it may not be effective at algae control (required dose is 22,000) or even Streptococcus bacteria (which requires 9000 and is on the low end of bacteria).

The moral of the story is to buy the biggest unit you can afford for your tank and run it less then 24/7 at the optimum gph to turnover your tank contents 2x a day. On a 125g tank you could run it 24/7 at 100gph using a 30w unit and have optimal conditions for killing algae & most bacteria. Or you could get a 64w unit, run it at 275gph for 8.5 hours a day and achieve the same effect. The cost of the 30w unit is $100 or $200 less then a 64w unit. But the bulbs are almost the same price, say $50. And you will use the 30w bulb up 3x faster then the 64w bulb. So since you should replace the bulb every 6 months you will be replacing 3 of the 30w bulbs every 1.5 years and only replacing 1 of the 64w bulbs every 1.5 years. So the 64w unit will pay for the difference in initial cost in about a year and a half. After that the 64w unit is saving you cash over the 30w.


oh ok bro.....gotcha! ;)

in regard to run time....I still believe 24/7 should be the practice. Once you turn it off.....bacteria/pathogens,parasites...which were still present in your tank....will be able to multiply in numbers. Thus, the sole purpose (lessening and preventing bacterial/parasitical blooms) of your effective UVC was not achieved. Then you are again back to square one. Cuz no matter how big your wattage of your UVC is........not all pathogens are killed, since there are some "dead spots" in your tank. Some pathogens/bacterias/parasites/etc.....are on those "dead spots" in your tank.....and the water didnt go thru the effective 64-200 watt UVC. An effective UVC....will only lessen the numbers of pathogens in your tank....but WILL NOT COMPLETELY ELIMINATE them, even if you turn on your uvc 24/7. It will also just prevent break-outs/bacterial blooms in your tank

anyways, this chart I provided on my older posts which is provided by dr. foster and smith....gives a hobbyist a general idea of the wattage you'll need- and the proper flow rates to adjust your pump to- when using a sterilizer for controlling bacteria/algae and for controlling parasites

UV bulb ===== maximum flow rate to control =====aquarium size
____________bacteria & algae == ==parasites
8w---------------120 gph------------n/a -------------under 75gal
15w--------------230 gph-----------75 gph -----------75 gal
18w--------------300 gph-----------100 gph ----------100 gal
25w--------------475 gph-----------150 gph ----------150 gal
30w--------------525 gph-----------175 gph ----------175 gal
40w--------------940 gph -----------300 gph----------300 gal
65w--------------1700 gph---------- 570 gph ---------570 gal
80w--------------1885 gph-----------625 gph ---------626 gal
120w-------------3200 gph-----------900 gph ---------900 gal
130w-------------3400 gph----------1140 gph --------1140 gal


not anecdotal........i got it from their research/links.........

Even intellectual scientist disagree on their findings..........and have different results. It will now depend on the hobbyists like us who to believe....

How I wish...I got money to spend on a 64 watt UVC. too bad, I cant...hehehe! Maybe someday. :)

Dave C
07-30-2005, 12:01 PM
Perhaps you're missing the point I was making in my comparison of a 30w & a 64w. It takes about 24 hours at 100gph to turnover the contents of a 125g tank 2x. It takes about 8 hours at 275gph. So whether you use a 30w bulb at 100gph or a 64w bulb at 275gph you're doing the exact same thing, turning over 99.99% of your tank water 2x a day. If there are dead spots in your tank they exist under both scenarios and you don't accomplish anything greater by running at a slower gph for a longer period of time. So the result is the same under both scenarios... but it's much cheaper in the long run to do it for 8 hours a day at 64w then 24 at 30w. That makes the 64w unit free over the course of many years.

The premise of the 2x turnover is that you are entirely wiping out the bacteria in your tank 2x a day by turning over the tank 2x a day. If you read the book you'll see where Escobal discusses the time it takes for bacteria to reproduce and how he arrives at the optimal turnover of 2x a day. The idea is that by achieving this you do remove 99.99% of freefloating bacteria in your tank. Of course you do nothing about bacteria that sits on the fish, on the tank walls, bottom, substrate & in your filter. That's why your tank is not "sterile", but your water certainly can be.

john2gs
07-30-2005, 12:12 PM
ok bro..i got your point on the bulb thingy now......sorry, hehehe!

Oh about the 99.99% elimination....I still doubt that. Probably 90% eliminated only........cuz again, there are dead spots in a tank........and there is no guarantee that the whole tank water goes thru the UV chamber.....especially if the turn over rate of the total tank water is twice a day. And chances of bacteria reproducing/multiplying, will still be promising....at a 2 x turn over rate.


I guess to increase the chances of bacterial/pathogenic elimination to 99.99% .....instead of having only 1 VERY effective UVC zapper (slow gph and Higher watts UVC for example) .......add more UVCs!!!. That for sure will be the REAL DEAL .....since the passing thru of water that has free-floating stuff...to multiple UVCs...will definitely increase. And the total tank water passing thru...will then be probably achieved......

Dave C
07-30-2005, 12:25 PM
Actually I believe a more effective solution would be to change water frequently, quarantine new arrivals properly, don't overfeed or overstock, thoroughly vacuum the tank bottom and skip the UV. The biggest problem I had with UV is that there is no way to know if it's effective, other then with algae. You can visually tell if your green water goes away but you cannot tell if your fish are benefitinig from bacteria reduction. I used UV for 3 years and I have no fewer deaths or disease using UV compared to not using it. Another issue that many hobbyists face is that because they don't visually see any difference using UV compared to not using it, they don't replace the bulbs as often as they should. Many just replace them when they burn out. So I can't prove to you that the flow rate & bulb size you're using is ineffective for your tank, but you can't prove that it's effective. If it works for you & you're happy then that's great. But for perspective UV buyers I suggest you reconsider your need for a UV sterilizer. While I don't believe UV does any harm I also didn't see any benefit to using it other then reduction of green water.

john2gs
07-30-2005, 12:31 PM
Actually I believe a more effective solution would be to change water frequently, quarantine new arrivals properly, don't overfeed or overstock, thoroughly vacuum the tank bottom and skip the UV. The biggest problem I had with UV is that there is no way to know if it's effective, other then with algae. You can visually tell if your green water goes away but you cannot tell if your fish are benefitinig from bacteria reduction. I used UV for 3 years and I have no fewer deaths or disease using UV compared to not using it. Another issue that many hobbyists face is that because they don't visually see any difference using UV compared to not using it, they don't replace the bulbs as often as they should. Many just replace them when they burn out. So I can't prove to you that the flow rate & bulb size you're using is ineffective for your tank, but you can't prove that it's effective. If it works for you & you're happy then that's great. But for perspective UV buyers I suggest you reconsider your need for a UV sterilizer. While I don't believe UV does any harm I also didn't see any benefit to using it other then reduction of green water.

I agree with what you stated bro. Alot of hobbyist think that since UVC was installed...cleaning and doing water changes should be less.....which shouldnt be the case. Plus you are right...they wait until the uv bulb gets busted..before replacing them. I usually replace mine within 6 months.

Actually, I can honestly say that I also dont know, if bacteria and pathogens are killed...during my usage of UVC.........and benefiting my fish. But I guess....I am believing in some research so much........and tend to just use it...since there is no harm in using it in the tank, in the first place. As a hobbyist, i am MORE rest assured that my fish are not gonna be experiencing bacterial/pathogen problems....since I have the UVC......but thats just me. :)

Dave C
07-30-2005, 12:37 PM
Don't get me wrong, I have no doubt that a UV sterilizer will kill bacteria, algae & parasites in an aquarium. I just don't know if it's necessary for the health of your fish if you quarantine, don't overfeed/overstock etc. It hasn't been necessary in my tanks and for the cost I can think of better things to do with my money then buy something that may or may not have any effect.

john2gs
07-30-2005, 12:40 PM
Don't get me wrong, I have no doubt that a UV sterilizer will kill bacteria, algae & parasites in an aquarium. I just don't know if it's necessary for the health of your fish if you quarantine, don't overfeed/overstock etc. It hasn't been necessary in my tanks and for the cost I can think of better things to do with my money then buy something that may or may not have any effect.

hehehe...thats why I just use a cheap 13 watt uvc....hehehe! I rather spend more money w/ filtration ;)

lets just hope that these UVCs....really help the health of our fish :)

Organic Farmer
07-30-2005, 07:07 PM
wow thanks for everybodys reply thats alot of info now as if i did not stir things up enough. Do i take a chance on making my fish infertile if i run my unit 24-7 ? again thanks to everyone and i plan on spending all my free time here

john2gs
07-30-2005, 08:07 PM
wow thanks for everybodys reply thats alot of info now as if i did not stir things up enough. Do i take a chance on making my fish infertile if i run my unit 24-7 ? again thanks to everyone and i plan on spending all my free time here

dont worry about it bro. Your fish is not directly exposed to the UV light...especially if you buy a UVC which is outside your tank.

Tad
07-31-2005, 11:22 PM
IMO UVs are unnecessary! I've used them in the past and havent seen anything dramatically beneficial, IMO that warrants their use. I could however see the use of one on a hospital tank to eliminate some bacterial issues when dealing with sick/compromised fish and helping them along with their recovery, but that again is just MO!,

Regards,
Tad