Light question

[gwhook]

I have found some lights saying the use PL lamps and some say T5 what is the difference? The PL seem to have higher output in watts.

 

[CoryC]

What's don't always equal PAR. Not sure what you mean by pl lamps though, are you talking about power compacts? They were used for many years, some people still use them but you can get better par with almost as much wattage with a t5/halide combo, or similar par with lower wattage through LEDs. I use halide and led with great results.

 

[EvilMel]

...and PAR isn't everything.

I also think that PL lights are some kind of compact fluorescent. The compact fluorescent bulbs are usually more expensive to buy and more expensive to run (electricity usage-wise, I mean). My RSM has two higher output compact fluorescent bulbs and they do really well for the corals in that tank (and for the algae too).

 

[CoryC]

What else is there in a light source? Color spectrum?

 

[CoryC]

Photosynthetically active radiation, often abbreviated PAR, designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis. This spectral region corresponds more or less with the range of light visible to the human eye.

If a light source can't appropriately and efficiently replicate PAR values coral needs to grow, then the ancillary issues with types of lighting are irrelevant because without x PAR at x Depth, coral cannot grow.

 

[EvilMel]

What I meant was that people often use PAR values to indicate that their lights are superior e.g. "this light gives blah blah PAR

Lights with the same PAR values often do not result in the same coloration or growth of corals. What is theoretically true often is not actually true in practice.

 

[nitrox36]

Lol