T5 vs. MH

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What is the difference between a 10000K T5 and metal halide of the same Kelvin rating, other than the obvious power rating difference and globe type?
 
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mh can penetrate deeper.
mh give of more heat.
a t5 globe would cover more area than a mh, well that depends how high the mh is.

thats all i can come up with. maybe the one looses its par quicker?
hence t5's get replaced soon than mh globes?
 
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mh can penetrate deeper.
mh give of more heat.
a t5 globe would cover more area than a mh, well that depends how high the mh is.

thats all i can come up with. maybe the one looses its par quicker?
hence t5's get replaced soon than mh globes?
Ok, so if I have SPS at 200mm below the lights what difference would there be between the the T5 and MH, regarding coral health and growth ?
 
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May not give the same colour depending on ballast of MH, PAR rating on MH should be much higher. Think time to replace MH globe is extended to that of T5. PLus you just need a lot more T5s.


(EDITED: Gaz beats me again.)
Ok lets say both techs are actually the same 10000K rating, what is the difference to an SPS corsal 200mm away from either lighting tech ?
 
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that i have no clue, sorry but maybe some of the gurus can step in here

trad you to slow today:p
 

viper357

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Good old Iwan - he's been a legend for a couple of years. Unlike our local Ivan :p
 
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What is the difference between a 10000K T5 and metal halide of the same Kelvin rating, other than the obvious power rating difference and globe type?
I am no guru. Not by a long shot. But in laymen s terms we also have a measure of the energy of light ie photon ....Can be seen as a packet of energy/light. There are a few other reference to light measurement. Color spectrum is only one part. PAR (photosynthetic available radiation) is the critical one... as photosynthesis occurs in a very specific wavelength. This measurement takes into account the energy aspect as well and is easy to understand.

I have tried to read Sanjay Joshi s threads (the supreme lighting guru), but i am frequently left bogged down with technical bits and bobs; so normally just skip to the conclusions.

So in conclusion. A candle has a Kelvin rating of around 600k. Two candles will still have a Kelvin rating of 600K and so will a 100 candles. But the energy radiated will increase incrementally.
And so the difference between T5 and halide can be easily seen.

SPS have evolved in high energy zones. Shallow surf areas, heaps of light + oxygen and massive turbulence.

I am a supporter of T5 Lighting but for sps....Hmmmmm...... there is a gap in my education
 
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I have also tried to read through these technical threads. The real difference they seem to agree on is when 20000K MH are used, but it seems undecided which is better in the 10000K options.

Also interesting how quite a few corals propagated under the different options all look very similar once lit up under 20000K lights.

Another interesting topic is how corals colour up to actually protect themselves from huge amounts of radiation (20000K)

Quite ironic the more beautiful they look the more under attack the coral is.

I am seeing more and more beautiful reefs (online) being sustained under T5's, this is the reason for my questioning the 10000K MH's.
 
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