The Differences Of Lighting

[RadaR]

A question I have been pondering on for a while. Im sure you saltwater hardware lads can help give me an intelligent answer.
What is the difference between having 100W of T8 lighting consisting of white&actinic bulbs, and that of having a 100W metal halide? Besides the apperance is there anything better that the halide has over the T8s? They are the same number of watts but I am right in assuming that halides are generally better? Could the difference be lumens?
Many thanks guys.

 

[boshank23]

i think the answer may be penetration (easy tiger) if you have whites and actinic tubes the white light penetrates less depth than the actinic. if you had a 14,000K you would get a much more even penetration.

don't quote me on that mind!

 

[SkiFletch]

Technically it's PAR that we aquarists are most concerned with (Photosynthetically Available Radiation), lumens is a useless measure to us. Lumens gives us an "idea" of how the lamp will perform, but a lumen could be a wavelength that our corals could care less about .

Because of their construction, halides can produce much more PAR than T8s. T5HO lamps are basically in the same playing field when it comes to PAR output versus wattage used, but T8 is not a very efficient technology. If you run the numbers, its six and one half dozen of the other when comparing halides with T5s. Both have advantages over the other and ultimately a choice between the two is up to the individual aquarist.

What boshank is referring to is color temperature. Generally 10000K lamps put out more PAR than 14000K and more still than 20000K. 10K look more white/yellow while 14K look blue/white and 20k usually look really blue. So you sacrifice photosynthesis for color; or you slap on a bunch of extra 20K bulbs with a handful of whites to sacrifice electricity for color AND photosynthesis

 

[RadaR]

Thank you both.
Just the replies I needed aswell
boshank23, nice to see someone relatively local.

 

[pengy666]

How local is this then

Somerset!!

Oh and imho

all the science aside you cannot compare T8 and halides,