uv sterilizers

[Organic Farmer]

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]

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]

thank you for your time ill give it a shot and let you know how it goes

[Cosmo]

mine run for about 20 hours a day, 365 days a year (sometimes 366 )

No ill effects

Jim

[Organic Farmer]

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]

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]

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]

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

[john2gs]

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

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]

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]

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]

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]

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/showquesti...Auto=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]

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/showquesti...Auto=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]

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...glance&s=books