LED UV, is it a farce, lets discuss

Discussion in 'Lighting' started by dallasg, 13 Jan 2013.

  1. dallasg

    dallasg Moderator MASA Contributor

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    So here is my debate for the weekend, after speaking to people in the LED unit market, doing some research, reading and some logic: is there any use for UV in corals.

    LED unit hype is all about UV now and yet I can't find anything showing the need, seen a few articles where chlorophyll stops above UV, T5 globes don't emit UV and we filter it out from Metal Halides, have I missed something

    Will post links once we get a discussion going
     
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  3. Marine1

    Marine1

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    following as the vertex unit has brought out UV pads and I would also like to know what the benefits are?????
     
  4. dallasg

    dallasg Thread Starter Moderator MASA Contributor

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    Well I am waiting for permission to post replies I have, and getting more info from the experts like Sanjay Joshi
     
  5. Nemos Janitor

    Nemos Janitor

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    Which UV are we going to talk about UV-A UV-B UV-C or UVR.....

    Glass shields in halide lights only shelled out UV-B and UV-C. UV-C is the UV used in UV steriliser units. So I assume we talk about UV-A and UVR.
     
    Last edited: 13 Jan 2013
  6. dallasg

    dallasg Thread Starter Moderator MASA Contributor

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    Well that I leave for discussion, yes UV-A is what we want
    Lets get the creative juices flowing
     
  7. Nemos Janitor

    Nemos Janitor

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    When I first joined MASA Rob and I had a discussion on the manipulating of coral colour by changing the UV spectrum. Most zooxanthellae produce UVR blocking pigments. These pigments (colour) change when the UV wave length changes. It is thought that most corals use the wavelength between 350 and 400nm Some say the band is a lot narrower 360 - to 380nm.
     
    Last edited: 13 Jan 2013
  8. carlosdeandrade

    carlosdeandrade

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    Radions too, except not in pads!
     
  9. viper357

    viper357 Admin MASA Contributor

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    What is UV-A and why do we want it?
     
  10. dallasg

    dallasg Thread Starter Moderator MASA Contributor

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    Here is a reply I got
     
  11. carlosdeandrade

    carlosdeandrade

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    Corals produce pigments like blue, purple and pink to protect their DNA and RNA, which is damaged by UV-A and UV-B.
     
    Last edited: 13 Jan 2013
  12. carlosdeandrade

    carlosdeandrade

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  13. dallasg

    dallasg Thread Starter Moderator MASA Contributor

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    More
     
  14. RocketRooster

    RocketRooster

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    And of course the pigments flouresce as well under uv.

    Eta- beat me to it!
     
    Last edited: 13 Jan 2013
  15. Nemos Janitor

    Nemos Janitor

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    UV-A is from 320 - 400nm
    UV-B is from 280 - 320nm
    UV-C is from 200 - 280nm

    UVR is uv radiation

    Most UV-C is filtered out by the ozone layer and does not reach the reefs or earth. This UV is used for sterilisation etc

    Some UV-B reaches the reefs but it is filtered out by glass and water. Very small amounts reach the corals.

    UV-A reaches the corals and the pigments in the Zooxanthellae shield the coral. Too much UV and the coral burns to little and the zooxanthellae bleaches.

    This is where I think Dallis is hoping this thread will head.
     
  16. carlosdeandrade

    carlosdeandrade

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    Ok so here is another question, why do units that don't contain UV leds, and if they are strong enough, why does that also bleach corals?
     
  17. dallasg

    dallasg Thread Starter Moderator MASA Contributor

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    And T5's with no UV also grow corals well
     
  18. Nemos Janitor

    Nemos Janitor

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    Because the coral is not getting UV
     
  19. Nemos Janitor

    Nemos Janitor

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    T5 emit UV because they contain mercury.
     
    Last edited: 13 Jan 2013
  20. carlosdeandrade

    carlosdeandrade

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    Last edited: 13 Jan 2013
  21. Nemos Janitor

    Nemos Janitor

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