Purple Montipora digitata colouration!

  1. Vanny

    Vanny New Member Member

    Hi folks,
    I bought a purple digitata about 2 months ago and it started looking like this:
    [​IMG]
    a very nice purple colour
    at that time I had:
    1 x 30w 20000k led
    1 x 10w actinic and 10000k combined
    1 x 30w 10000k stock florescent tube

    the lighting could not meet the coral lighting requirements so it turned brownish/red but still grew

    then I switched to 234wat t5ho set up
    (currently running 3 x actinics and 2 x 12000k and the other 12000k light I took out due to algae bloom)

    now after 2 months since purchase the coral looks like:
    [​IMG]

    im not sure if it is bleaching or turning back to purple
    any suggestions
    I am contemplating also adding back the 20000k led 30w (really intense) to the mix of lights

    I dose calcium, strontium, magnesium, iodine, boron, .....
    also dose carbon (vodka regularly)
    phosphate, nitrate and ammonia all in check
    also have overated protein skimmer, and sump where I grow chaetomorpha algae
     
  2. RogueAgent94

    RogueAgent94 Fishlore VIP Member

    Welcome to Fishlore! :;toast

    That coral looks perfectly healthy to me. From what I have read and seen it seems that corals in one tank rarely grow the same color or look the same color in another tank. Zoanthids for example regularly change color from one tank to another. I'm not sure why.

    Also, in regards to your lighting, most coral aquaculturers often have more actinics than daylights. I read that in a 5 T5 fixture most people will keep 4 actinics and 1 daylight. So you might want to add an additional actinic light. There are several types from what I've seen. I'm in the process of building my own LED fixture and I am using Royal Blues, Deep Blues, and normal actinics. You could also put in a UV bulb if you wanted. Some corals appreciate the purple light.
     
  3. ryanr

    ryanr Fishlore Legend Member

    Hi, welcome to Fishlore :;hi2

    I'll preface the following by stating that SPS are the hardest corals to keep alive. That you have good growth indicates things should be ok water wise.

    I tend to agree that it looks healthy. Nature is constantly evolving and changing, plus, per Rogue, actinics can make all the difference in appearance.

    If the coral is indeed bleaching, check your temperature. Rising temperatures can cause bleaching events. It's one of the main causes for bleaching on our reefs (rising sea temperatures).

    What are your actual readings for:
    Alkalinity
    Calcium
    Magnesium
    Nitrate
    Phosphate
    Salinity