Metal Halide Q&A

Discussion in 'Metal Halide Aquarium Lighting' started by Dingo, Feb 16, 2010.

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  1. Dingo

    Dingo Giant Squid

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    I see we have a T5 Q&A but not a MH Q&A so I am hoping that this can take off like the T5 did...

    I have a lot of information on halide bulbs, ballasts, and fixture types so I would be happy to answer any questions :)
     
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  3. steve wright

    steve wright Super Moderator Staff Member

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    This is a cool idea Dingo

    Ill ask the 1st questions

    is there a formula that tells you what wattage lamps you would be best using?

    is there a formula that tells you how high the lamps should be positioned above the tank and is that also dependant on wattage?



    Steve
     
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  4. Dingo

    Dingo Giant Squid

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    Good question steve!
    I do not have a formula, however there is a logic behind what wattage should be chosen for a tank. The higher the watts of a bulb, the more photons it can put out --> this means that the light will maintain a higher PAR at further depths.
    under 20"- 175 watts
    20-30"- 250 watts
    +30"- 400 watts
    The closer to the tank that you keep the lights, the higher your PAR will be, however, this produces a lot of heat on the water and can cause overheating of the tank
     
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  5. sollie7

    sollie7 Millepora

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    are MHs alot hotter then PCs?
     
  6. RNO CORALS

    RNO CORALS Bristle Worm

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    Not even compareable. you can touch a PC, a MH will burn you.
     
  7. patrick824

    patrick824 Montipora Digitata

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    YES they are much much hotter.
     
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  9. jonjonwells

    jonjonwells Great Blue Whale

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    Mounting height:

    I would have to say that the height depends more on your reflectors efficiency than your wattage rating. A Lumen Bright, for instance, has a very specific mounting height.

    Wattage:

    70 Watt under 15"
     
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  10. Dingo

    Dingo Giant Squid

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    Yes they are. The heat is from the infrared radiation that MH bulbs give off. This type of light is not visible to human eyes, nor is it harmful. It has high energy and low frequency, therefore is easily turned into heat

    It is associated with wavelengths above 750 nm
     
  11. sollie7

    sollie7 Millepora

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    so if i switched to mh it would heat my tank up way more?
     
  12. RNO CORALS

    RNO CORALS Bristle Worm

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