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How many hours for metal halide on?

Discussion in 'General Discussion' started by mr.jeff.wagner, Jan 8, 2008.

  1. mr.jeff.wagner

    mr.jeff.wagner Inactive User

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    I just got a metal halide... 175 watts, 14K bulb... Just wondering how long you guys think i should have this on during the day?  I am also adding 2 65W PC actinic bulbs that will probably be on all day.
    I usually have my PCs on for 12 hours, so can I do 10 hours or just 8 or less?
  2. einsteins

    einsteins Experienced Reefkeeper

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    I would start conservative as MH are quite a bit more intense than PC's
    It is key to watch how your corals react to the more intense light. if they appear to be fading or polyps are not out then you might want to either shorten the light cycle or if its just one coral move it deeper in the tank.

    Give them plenty of time to adjust....many people burn their corals (especially the ones higher in the tank) when they first get MH.

  3. slovan

    slovan Experienced Reefkeeper

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    I agree with einsteins about acclimating your corals to your new lights. Photoperiod will vary from tank to tank. It's almost trial and error and personal preference when it comes to photoperiod. I have my MH on for 6.5 hours a day and actinics on for 9 hours. Some do more and others do less. However I think the canned response is 8 hours a day.

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