To UV or not to UV??

[Catpicklesdog]

That is the question!!

Ever since I've had a pond I've always run a UV filter, it's a must, to keep green water at bay.

However, I have never run one on any of my tanks.

This thread is for discussing the pros and cons of having a UV, not to say who is wrong or right!!

Have you used one and what are your experiences?

 

[The Zigman]

I run one on my 125 discus tank...
I noticed some white ick looking spots on a few of my new additions...
particularly my baby clown loaches. Within a couple days they were gone. Dont know if it was from the turbo twist (or the 86F water!) .. but I am sure it helps. the only bacteria it will kill is what passes through it, and is exposed to the uv long enough to be killed. since most of the biofilter organisms live in the filter, they wont be hurt by the UV.
I never have "green water"

I thought it was pretty much Standard equipment on a SW tank?

 

[Catpicklesdog]

I run one on my 125 discus tank...
I noticed some white ick looking spots on a few of my new additions...
particularly my baby clown loaches. Within a couple days they were gone. Dont know if it was from the turbo twist (or the 86F water!) .. but I am sure it helps. the only bacteria it will kill is what passes through it, and is exposed to the uv long enough to be killed. since most of the biofilter organisms live in the filter, they wont be hurt by the UV.
I never have "green water"

I thought it was pretty much Standard equipment on a SW tank?[/quote]


Not really. A lot of people say it kills any beneficial bacteria which is why I thought it would be good to start a thread to find out all the pros and cons. I've always been told not to have one on a SW tank whereas on a pond it's necessary. It was only when upgrading my pond that I've started giving it more thought to have one on my tank!

 

[irishspy]

I've always been told not to have one on a SW tank whereas on a pond it's necessary.

That's interesting. Many years ago, I worked for an aquarium maintenance service, and a UV unit (much cruder then) was considered a luxury, but a darned good one to have on marine tanks.

What bacteria would be in the water column of a saltwater tank that you shouldn't want to use a UV unit?

 

[Amphiprion]

Well, bacteria (and associated substrates) happen to be one of the largest food sources for corals (one also rich in the macroelements). That being said, there is still usually a lot of bacteria in our systems. Beyond that, the only advantage I think a UV sterilizer has is the reduction of yellowing compounds in the water (though carbon can solve that problem AND remove them at the same time). The same could be said of ozone, except it is more effective on a number of different compounds. None of them are necessary (and arguably not even beneficial). My tank has crystal clear, colorless water without either. I simply use activated carbon, a protein skimmer, and a good phosphate remover.

 

[Fishieness]

Well, bacteria (and associated substrates) happen to be one of the largest food sources for corals (one also rich in the macroelements). That being said, there is still usually a lot of bacteria in our systems. Beyond that, the only advantage I think a UV sterilizer has is the reduction of yellowing compounds in the water (though carbon can solve that problem AND remove them at the same time). The same could be said of ozone, except it is more effective on a number of different compounds. None of them are necessary (and arguably not even beneficial). My tank has crystal clear, colorless water without either. I simply use activated carbon, a protein skimmer, and a good phosphate remover.

amen

 

[kcress]

Just seems wrong to me. There is no UV system in the oceans and we are, after all, trying to mimic the ocean in all the ways we can.

I used to have a UV but I always wondered if the cost was worth it and whether it was actually being effective. They certainly need painful maintenance to have a hope of success.

 

[Catpicklesdog]

Well, bacteria (and associated substrates) happen to be one of the largest food sources for corals (one also rich in the macroelements). That being said, there is still usually a lot of bacteria in our systems. Beyond that, the only advantage I think a UV sterilizer has is the reduction of yellowing compounds in the water (though carbon can solve that problem AND remove them at the same time). The same could be said of ozone, except it is more effective on a number of different compounds. None of them are necessary (and arguably not even beneficial). My tank has crystal clear, colorless water without either. I simply use activated carbon, a protein skimmer, and a good phosphate remover.

This is the kind of reasoning I'm looking for. It's also always been my view. I just thought it would be good to have a pros and cons list especially for any newbies to the hobby that have an LFS that might sell them anything! My LFS told me not to waste my money (he does know exactly how I run my tank though!!).

 

[Almondsaz]

I run a 25 watt Aqua UV on my 125 and the only reason I run it is for MI control. It won't do anything for infected animals, but it will remove MI from the water column. I run it the opposite of my fuge....only during the daylight hours and it is off when the tank is dark.

This can be a very emotive topic. I was dead against having one until I had MI and spoke with the marine maintenance man who did the plumbing for my tank and he runs one 24/7 and on a 300g full reef. He said he has done it for years and has no plans on stopping.

So for my experience I am happy that I have one and think you need to be careful on how big a one you get and how much you run it. There are those that buy a small one and use it on their QT system which makes a bit of sense as well.

 

[Amphiprion]

Actually, most units are incapable of killing Cryptocaryon in the water column. In order to actually accomplish that, you'd need a grossly oversized unit with a very slow flow-through rate. Most people don't have one nearly strong enough to kill organisms in the same size range as Cryptocaryon. Unfortunately, this is often very contrary to manufacturer's claims. At that range, it would also kill 'pod larvae, etc.

Out of curiosity, what things can this maintenance guy 100% attribute to the UV sterilizer--enough so that it would sway you to buy one?