uv and influance on chemicals

guy tillmans

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Jul 29, 2008
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I've read a lot of using a uv-filter (in-line). Every time, folks tak about the influance on chemicals we use in our tanks, Especially the influance on iron is mentioned. Uv (used permanently) should dissolve/break down the chelated coatings of the nutrients/iron. The result is that the iron is unusable for the plants. Is this right??
Second question is: What is the surplus value of an uv-filter for our tanks?? They kill only the floating algea, not the other alea in our tanks m such as fuzz or thread.
 

Tom Barr

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They kill pretty much whatever goes through them, so suspended al;gae spores or Green water is controlled.
Bacteria , cyst, disease propagules will also die.

As far as causing any noted effect on nutrients, trace iron dosing, this has never once been demonstrated or any noticable effect in anyones aquarium to date.

It's a very easy thing to test as well.
Turn UV on, say for 3 weeks, note plant health.
Turn UV off for the 3 weeks, note plant health.
Dose as normal.

Repeat this several times, say 6X.

Then you can be fairly sure what you see is more than likely to be due to UV effects on the traces.

But no one has.................nor seen any differences they can honestly attribute to solely the effect of UV on nutrients.

So while there's a theory...........it's not well supported by any observations by aquarist.

Perhaps it does break the chelated bond.............some spectra of UV dose do this, better than others.........the ones used for germicidal effects are typically different than those used for some chemical bond breaking.
Also, different chelators for Fe will have different bond strengths and thus also have different abilities to maintain chelation.

Fe typically does not last long in solution anyways, fortunately we do not need a lot, as far as I know, the rest of the nutrients are relatively unaffected.

So basically there is a lot of talk, discussion about the theory, but not one person has done much about verification or has there been any noted correlation between UV use and low Fe in a planted aquarium.

Too much talk, not enough good test.
I've never been able to see any differences to date.

And if the bond is broken, can the chelator rechelate the Fe?

Regards,
Tom Barr
 

hani

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Thanks for the answer, because i was thinking about it, should we use them routinly, did they have any benefit?
thanks
 

Gerryd

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Hi,

I was installing mine for overall benefits like Tom mentions:

They kill pretty much whatever goes through them, so suspended algae spores or Green water is controlled.
Bacteria , cyst, disease propagules will also die.

I didn't buy mine for a specific purpose, but had heard enough good things about them that I thought I would try one and see for myself.

Since I was redoing the system anyway, was a good time to incorporate it.

Not sure how much it will help my system, but I don't think it will hurt it in any way....
 

Tom Barr

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No, I use it 2 days a week to kill anything after I do the weekly trim/water change, the following two days the spores of algae or bacteria etc will flat around.

No need to run them all the time unless there's an issue.
Save the electrical cost and the bulb's life for when you really need them.


Regards,
tom Barr
 

Gerryd

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Tom,

That's a great idea to run it only those couple of days.

I had assumed that they were run 24/7 for some reason...........

I can set a timer to do this.......
 

yme

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reading old posts....

I wondered whether the regime of turning on uv after a waterchange is still a good idea in general. Threoretically, it makes a lot of sense... wiping the algae from the glass... uv.... destroys it...no additional settling of algae/spores on plant leaves.

But practically? has someone seem a difference with/without uv? just curious! :D

greets,

yme
 

Biollante

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Yes!

yme;42910 said:
reading old posts....

I wondered whether the regime of turning on uv after a waterchange is still a good idea in general. Threoretically, it makes a lot of sense... wiping the algae from the glass... uv.... destroys it...no additional settling of algae/spores on plant leaves.

But practically? has someone seem a difference with/without uv? just curious! :D

greets,

yme

Hi,

Yes.:)

Biollante
 

Tom Barr

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I see differences in some tanks, and not others personally.
They do not hurt and provide better conditions for fish.......

Better for plants?
The only thing might be breaking the bonds to allow/release more Fe perhaps(a long shot), but more likely for algae spores when we mess around and uproot, clean, water change etc.

So not much for plants really.

Regards,
Tom Barr
 

Biollante

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I Have A long Version

yme;42919 said:
short, but clear :D

thanks!

yme

Hi,


What Tom Barr said. :)

I see the main benefit of ultraviolet as water quality, principally benefiting the critters in the tank. The more sensitive the critter the more they seem to benefit.

I have run ultraviolet 24/7, with no negative effect, I used to run the ultraviolet 6 hours a day, but I really think 4-6 hours for a couple days after water changes is adequate in a healthy tank. ;)

I have a long version. :D

Biollante
 

The Rockster

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Aug 10, 2007
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Seachem Excel and UV Sterilizers

guy tillmans;28378 said:
I've read a lot of using a uv-filter (in-line). Every time, folks tak about the influance on chemicals we use in our tanks, Especially the influance on iron is mentioned. Uv (used permanently) should dissolve/break down the chelated coatings of the nutrients/iron. The result is that the iron is unusable for the plants. Is this right??
Second question is: What is the surplus value of an uv-filter for our tanks?? They kill only the floating algea, not the other alea in our tanks m such as fuzz or thread.

Hi,

I just got email from Seachem suggesting not to use the UV when dosing Seachem Excel.
Apparently it could break down the active ingredient.
 

The Rockster

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You Might Ask Seachem at their Forum......here is their post.

Tom Barr;44429 said:
Break down into what?:idea:

Regards,
Tom Barr

Here is the thread in which Seachem support claimed that Excel's main ingredient may break down with the use of a UV filter. That is all I reported here, as I was surprised, (first I heard of it) and thought others would be too. If in fact, this information is correct, and I would guess it is, then to be aware of this factor is in keeping with the thread topic.

http://www.seachem.com/support/forums/showthread.php?p=7476#post7476

"It is important to turn off your UV on days that you dose Flourish Excel, as UV could break down the active ingredient"

If I knew the answer to your question, I would gladly tell you. Having read most of all your posts on the net, going back years, we both know you are very well acquainted with Seachem and their CEO.