Reef Central Online Community

Go Back   Reef Central Online Community > Blogs > GeorgeMonnatJr
Blogs FAQ Calendar Mark Forums Read

Notices

  1. New Comment
    Posted 03/05/2016 at 01:38 AM by zohoki zohoki is offline
  2. New Comment
    Timfish's Avatar

    LEDs and PAR/Quantum Meters Part 2: PAR

    Quote:
    Originally Posted by GeorgeMonnatJr View Comment
    . . . I need to get all of the Sprung books (saw one at Half Price Books for $45, looked online and saw cheapest was around $200 on Amazon, went back to Half Price and it was gone. Did you snag it? )
    . . . a list of which coral groups use which zooxanthellae species and their specific action spectra. . . .
    No. I heard Delbeek & Sprungs books were going out of print but I was blown away by the prices on Amazon.

    Search Dana Riddle and Sanjay Joshi for more on fluorescing pigments, lighting and coral but there are certainly other researchers. Corals pick zooxanthellae partly on environmental cues so I doubt there's a strict correlation between coral and zooxanthellae sp.
    Posted 05/25/2012 at 08:56 PM by Timfish Timfish is offline
  3. New Comment
    GeorgeMonnatJr's Avatar

    LEDs and PAR/Quantum Meters Part 2: PAR

    Quote:
    Originally Posted by Timfish View Comment
    Another interesting datum is in some cases the red fluorescing some corals show is not done by pigments the coral produces or are produced by the zooxanthellae but by symbiotic cynobacteria with in the host cells.

    Delbeeck & Sprung "The Reef Aquarium" Vol III, pg 515
    Everything about coral and marine biology is still fascinating to me, so thank you for the comments.
    Posted 05/25/2012 at 09:42 AM by GeorgeMonnatJr GeorgeMonnatJr is offline
  4. New Comment
    GeorgeMonnatJr's Avatar

    LEDs and PAR/Quantum Meters Part 2: PAR

    Quote:
    Originally Posted by Timfish View Comment
    George, you are aware the zooxanthellae species are dinoflagellates in the genus Symbiodinium? Unless it can be specifically shown this genus does not use it this would seem to me to make chlorophyll C important for the survival of corals.

    Delbeck & Sprung, "The Marine Aquarium" Vol I pg 47 &
    http://en.wikipedia.org/wiki/Symbiodinium
    No, I'm admittedly ignorant of how corals "work". That's why I'm fascinated by and really appreciate any comments like yours by people who know better. I need to get all of the Sprung books (saw one at Half Price Books for $45, looked online and saw cheapest was around $200 on Amazon, went back to Half Price and it was gone. Did you snag it? )

    What I really need is a list of which coral groups use which zooxanthellae species and their specific action spectra. I'm fairly confident in saying that the deeper the ecological niche that a coral species inhabits, the less green-to-red light it needs to grow.
    Posted 05/25/2012 at 09:41 AM by GeorgeMonnatJr GeorgeMonnatJr is offline
  5. New Comment
    Timfish's Avatar

    LEDs and PAR/Quantum Meters Part 3: Quantum Sensors and LEDs

    George, I like this series about lighting! While you are focusing on the issue of getting PAR readings for LEDs I feel it is important to p[oint out the issue with Apogee PAR sensors underweights blue light and overweights red applies to every light source not just LEDs. If a PAR reading is taken of T5s it will underweight blue to the same degree it underweights blue light from an LED source. I have long complained what we need is an easy way for the average aquarist to get a spectral chart of the light at a specific location in a tank.
    Posted 05/24/2012 at 07:18 PM by Timfish Timfish is offline
  6. New Comment
    Timfish's Avatar

    LEDs and PAR/Quantum Meters Part 2: PAR

    Another interesting datum is in some cases the red fluorescing some corals show is not done by pigments the coral produces or are produced by the zooxanthellae but by symbiotic cynobacteria with in the host cells.

    Delbeeck & Sprung "The Reef Aquarium" Vol III, pg 515
    Posted 05/24/2012 at 06:53 PM by Timfish Timfish is offline
  7. New Comment
    GeorgeMonnatJr's Avatar

    LEDs and PAR/Quantum Meters Part 2: PAR

    F. favus Zooxanthellae Action Spectra

    In an attempt to answer my own questions above about coral spectra requirements, I found this reference.

    O. Levy*, Z. Dubinsky and Y. Achituv, The Journal of Experimental Biology, Photobehavior of stony corals: responses to light spectra and intensity, Accepted July 22, 2003, 09MAY2012



    Quote:
    Absorption characteristics of the major pigments extracted from F. favus zooxanthellae. Pigments are: Chl, chlorophyll; Chld, chlorophyllidae; Per, perdinin; Dia, diatoxanthin; Dino, diadinoxanthin.
    That chart and the one in my previous comment tell me you could use LEDs to provide light from about 430nm to 500nm but no light from 500nm to 650nm and effectively starve out the cyano without harming the coral. Or at least that would work for one kind of head coral.

    I'd still like a marine biologist/botanist to back me up - or even to refute what I'm saying.
    Posted 05/09/2012 at 03:26 PM by GeorgeMonnatJr GeorgeMonnatJr is offline
  8. New Comment
    GeorgeMonnatJr's Avatar

    LEDs and PAR/Quantum Meters Part 2: PAR

    Cyanobacteria Action Spectra

    I was researching cyanobacteria (cyano) and how to get rid of it after reading complaints, and I came across a great reference. I wish I wasn't at a character limit in the blog, but in the future I may rewrite it with this reference.

    Photosynthesis: Light energy transduced to chemical energy, Pigments and absorption spectra, updated 11/30/2008, 09MAY2012



    Quote:
    Phycobilins are water-soluble pigments, so they are found in the cytoplasm, or in the stroma of the chloroplast. Phycolibins occur in Cyanobacteria (phycocyanin and phycoerythrin) and the "red algae", the Rhodophyta (phycoerythrin).
    My conclusion from this is that cyano MUST have green-to-orange light (480nm - 640nm) to derive significant energy from photosynthesis. That is why old MH and florescent bulbs can cause cyano outbreaks - they have more green-to-orange light. Blue LEDs have none of that and "white" LEDs have less than MH.

    My question above still stands, does anyone know if corals need the green-to-orange light (480nm - 640nm)? If not, then with LEDs it should be very simple to starve out the cyano while still feeding coral. For comparative spectra of MH and LEDs, see Part 1 of my blog.
    Posted 05/09/2012 at 03:09 PM by GeorgeMonnatJr GeorgeMonnatJr is offline
  9. New Comment
    GeorgeMonnatJr's Avatar

    LEDs and PAR/Quantum Meters Part 3: Quantum Sensors and LEDs

    Quote:
    Originally Posted by mpc View Comment
    As I fear that coral bleaching with LEDs might concern me as well I would like to be able to at least evaluate the output they are giving. So your suggestion to get only a sensor is very appealing. Could you please clarify the key differences between SQ-110 and SQ120? I understand that the calibration procedure for these is different - 110 being calibrated against sunlight whereas 120 using an artificial lighting. Which one should people get ?

    Thank you!
    Both calibrations are done at the factory, so the user doesn't need to do it. It's really what you prefer as your reference, the sun or electric light. From what I can tell, the electric light calibration of the SQ-120 (page 7) is to sodium arc, MH, and/or CFL - not LEDs. I can understand not calibrating it to LEDs, because the variations are too numerous to list.

    Since I'm still a newbie concerning coral, when I was trying to decide which sensor to purchase, I looked through the forums and saw most people were using the SQ-110. Here are some examples.

    LED lighting and PAR measurements -- Advice?

    PAR meter around?

    LED PAR Readings

    That made sense to me, because we are concerned with replicating the sunlight that our livestock needs to grow. So I chose the SQ-110. If I had gone with MH instead of LEDs, it might have been a more difficult choice, but with LEDs I chose the sun as my reference.

    Thanks for asking. Because of your question I found more information on the Apogee site.
    Posted 05/05/2012 at 10:48 AM by GeorgeMonnatJr GeorgeMonnatJr is offline
  10. New Comment

    LEDs and PAR/Quantum Meters Part 3: Quantum Sensors and LEDs

    As I fear that coral bleaching with LEDs might concern me as well I would like to be able to at least evaluate the output they are giving. So your suggestion to get only a sensor is very appealing. Could you please clarify the key differences between SQ-110 and SQ120? I understand that the calibration procedure for these is different - 110 being calibrated against sunlight whereas 120 using an artificial lighting. Which one should people get ?

    Thank you!
    Posted 05/05/2012 at 05:52 AM by mpc mpc is offline
  11. New Comment
    GeorgeMonnatJr's Avatar

    LEDs and PAR/Quantum Meters Part 2: PAR

    I just stumbled on a great resource. This pdf describes in greater detail that's easy to understand the stuff I mentioned above.

    Emmanuel Boss (Guest Lecturer), The University of Maine: School of Marine Sciences: Maine In-situ Sound & Color (MISC) Lab, Light and biology in the ocean, posted 2006, 03MAY2012

    I was looking for normal PAR readings of the sun when I found it. I'll try to work it into my blog above, but I think I'm at or near the character limit.
    Posted 05/03/2012 at 12:31 PM by GeorgeMonnatJr GeorgeMonnatJr is offline

All times are GMT -6. The time now is 03:04 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Use of this web site is subject to the terms and conditions described in the user agreement.
Reef CentralTM Reef Central, LLC. Copyright ©1999-2022
User Alert System provided by Advanced User Tagging v3.3.0 (Pro) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.