sps polyp extention

Discussion in 'SPS Corals' started by grinder37, Nov 14, 2012.

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  1. Kevin_E

    Kevin_E Giant Squid

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    Question: Zoanthelle is found in polyps, correct? If so, wouldnt we want full extension for increased photosynthetic area? If so I'd think full extension is a positive, not a negative.
     
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  3. Daniel072

    Daniel072 Giant Squid

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    You have great looking pieces...this is true and you also speak the truth. With this being said, there are many, many species of acro that have very little polyp extension in our home aquariums. it depends on a lot of things. When I was keeping SPS, there were many pieces that had very little polyp extension but were fast growers. I also had a lot of them under 400 watt MH 10k bulbs .
     
  4. aquariumclown

    aquariumclown Astrea Snail

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    Yes they can still grow and survive, but it doesn't mean they are at their optimal. The misconception is that the lights are causing the polyps to not extend.


     
  5. newtosalt

    newtosalt Spaghetti Worm

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    this is for fsukum Zoanthelle is mostly found in the tissue of coral. Its a algae that lives in the coral on acros and other corals polyps that come out are for filter feeding. if you watch really close they come in and out as the catch food, that is why most during the day they are inside safe but the coral is still feeding. full pe during the day could mean not enough lighting ime.
     
  6. Daniel072

    Daniel072 Giant Squid

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    Exactly
     
  7. m2434

    m2434 Giant Squid

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    Or too much. There has been research on polyp extension and it is not considered a reliable indicator of coral health. There are circumstances where it does indicate something wrong, however these circumstances will tend to also reduce growth and color. Growth and color are more reliable indicators, so if they are good that says a lot. Peronally I've had corals stop showing polyp extension and then rtn/stn, but suddenly start showing polyp extension and then rtn too. And some of my oldest, fastest growing, most colorful basically never show PE, but at this point, I would probably worry if the did :)
     
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  9. Corailline

    Corailline Super Moderator

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    +1

    Growth and color and I will add type.

    I would not get too wrapped up in PE and it's significance if a coral has good color and growth.
     
  10. grinder37

    grinder37 Whip-Lash Squid

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    Funny you mention this Matt,my BOP,which was the furriest frag left) still looked awesome until the lights came one the following day,a few chunks of flaking flesh is all that was left.Funny though,the ones doing well are mostly the high colored smooth skinned acros along with a few others.However,still no signs of PE,but growth,not much but noticeable.
     
  11. m2434

    m2434 Giant Squid

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    You know if you really want to make your brain hurt, read the literature. For example, Crossland and Barnes (1977) "Gas-Exchange Studies with the Staghorn Coral Acropora acuminata and Its Zooxanthellae" suggested that buildup of O2 from photosynthesis is toxic to corals, and corals may retract polyps to shade themselves and protect themselves from light under high irradiance. On the other hand Levy et. al (2003) "Diurnal polyp expansion behavior in stony corals may enhance carbon availability for symbionts photosynthesis" suggested that buildup of O2 from photosynthesis is toxic to corals, and corals may expand polyps to allow for gas exchange to reduce build up of O2 levels and allow additional intake of CO2, as coral metabolism alone, in some cases may not produce enough.

    The articles sort of make my brain hurt, but I think I can safely summarize them by saying "it depends on the coral" :)
     
  12. grinder37

    grinder37 Whip-Lash Squid

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    LOL,i'll go with your summary.I bought a big frag pack of assorted sps,threw them into an unmatured tank,then blasted with too much light.Some are gonna make it fine,some didn't and/or won't.Thats about it and as stated in the beginning of the thread,I already was expecting that.And I can accept it.;) Thanks again M2434