MH Height question

Discussion in 'Lighting' started by FransSny, 26 Mar 2010.

  1. FransSny

    FransSny

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    Hi guy , need to finally suspend my 250 W MH pendant over the coral display tank (600 mm deep), and would like some input from the lighting gurus.

    I built eggcrate stands inside the tank to increase the amount of corals I can place inside the tank, with the highest "shelf" being about 250 mm from top water level.

    I am planning to suspend the MH 300 mm from water level, would this be ok ?

    O yes, top shelves will be keeping SPS & lower, LPS , Softies
     
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  3. davidfr7

    davidfr7

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    Tagging along on this one. Frans what k is your 250w MH ?
     
  4. FransSny

    FransSny Thread Starter

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    Oops should have mentioned that 14 K. Normally I would hang it bout 300 mm but with the shelves ....not sure.

    No other lights will be used
     
  5. jacquesb

    jacquesb Retired Moderator

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    Hi Frans - here's my opinion:

    IF you can put the Metal Halide on a retractable cable, this would be 1st prize. Meaning, that I would start off much higher in the beginning, until the corals have gotten used to the 250 watt lighting blast.

    Just a quick question - I presume that this is/would be for your corals-to-sell/lifestock, right?

    If so - taken into account that the corals you get would be "light starved" (and slightly more "accustomed" to lower light) at the time that you place them into the display tank, then having a 250 watt metal halide blast them with light might just give the corals a light shock.

    So - if you can raise the 250 watt as soon as you receive the corals - and then slowly over a few hours or day/2 drop the unit lower and lower - then the corals will have a much better chance of surviving.....

    Just my 2 cents - for whatever it is worth... ;)
     
  6. davidfr7

    davidfr7

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    I have seen this at Idol were there lights can be 1m above the water. A few weeks later they have dropped down again.

    I would like to hear what Bob has to say?
     
  7. JD167

    JD167

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    Nice idea Jacques. Mine are 30cm from the surface of the water. But like Jacques said, it would be a better idea if you could suspend them from the roof and be able to move them up and down as needed.
     
  8. maj

    maj

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    so the coral tank will be ready soon i presume?
    the retractable idea is cool,and defnitly a handy one
     
  9. brentv

    brentv

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    My 250w 14k's are 15cm from the tank... all is happy!:)
     
  10. FransSny

    FransSny Thread Starter

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    Yes I agree JD, my problem is I have a rhinoboard ceiling.....cant suspend from there

    Totally agree JB....or I need to get a dimmable ballast ....My idea is to maybe make a adjustable arm, working more or less like an beach umbrella ?
     
  11. jacquesb

    jacquesb Retired Moderator

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    The adjustable arm is a very good idea, Frans. Can you "attach" the "arms" to the tank stand somehow?
     
  12. FransSny

    FransSny Thread Starter

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    Nope ...unless you would like to help move that moerse corner unit. Thinking of using 1/2 round brackets attached to the back wall
     
  13. jacquesb

    jacquesb Retired Moderator

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    OK cool - that too can work. What about the L-shaped brackets, used to support table-tops/counter tops/racks?

    You could possibly then attach pulleys to these brackets, and have a round "tie-back" "thingy" fitted to the wall, which you can then use to "tie" the cable of the lighting/lighting-unit to?

    I hope you understand what I am trying to get at?
     
  14. brentv

    brentv

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    Frans i've done this
    [​IMG]
    [​IMG]
    My lights have a bracket on the back wall and I can raise them at an angle.
    they are 250w MH fittings called reeflite, I paid R1100 ea.
     
  15. SIMS

    SIMS

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    I think those will burn the corals...
     
  16. brentv

    brentv

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    Nope they are 14k, they've been running for 3 months so far all corals are happy, also using a couple of T5 atinics for early morning acclimitization and evening viewing.
    [​IMG]
     
  17. jacquesb

    jacquesb Retired Moderator

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    Looking awesome there, Brent. Brent - do you perhaps have your Metal Halides on timers?

    With that setup, you could have a very nice "sunrise/sunset and midday" effect, by having the 4 x 250 watt metal halides switch on and off at different times - where all 4 is on for about 2 hours during the 12pm to 2pm time-line....
     
  18. JD167

    JD167

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    Frans, what about using some of those shelving brackets? Similar to the ones you currently use for the shelves in the shop. Attach the poles with the slots high up against the wall and clip in two of those triangular brackets. You can then suspend the lights from them.
     
  19. jacquesb

    jacquesb Retired Moderator

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    LOL JD! Great minds think alike, hey! ;) :slayer: :thumbup: ;)
     
  20. FransSny

    FransSny Thread Starter

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    Thanx guys....seems Im of to builders in a little while !
     
  21. JD167

    JD167

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    LOL yea. When I walk into Builders Warehouse I normally think "How can I incorporate that into my system to make it better...." ;)
     
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