Post by Carl on Oct 13, 2017 9:38:16 GMT -5
I updated this important article from "Aquarium/Pond Answers" again
Here is an excerpt:
"Summary
Hopefully readers come away after reading this article and its many cited resources with a better understanding of PUR/quality of light, not that I am stating certain LEDs or other lights in particular CANNOT keep photosynthetic life.
As well I am NOT stating that if a fixture uses green emitters it is a poor light.
In fact, green light has some proven applications in a closed environment for more growth when under 24% of overall light spectrum as well as producing a more pleasing overall light when part of the spectrum (as well as some synergy of all light spectrums). However a fixture that is heavier in the green spectrums is going to be less efficient for photosynthetic growth and possibly detrimental when over 25% of the overall spectrum as per cited .edu references.
I will also add that one has to look at the preponderance of evidence, both from .edu websites, NOVA, and similar sources as well as practical experiments and use COMMON SENSE that if one theoretical article comes to different conclusions, but the preponderance says otherwise, that we need to go with what in the end the majority of evidence states (not that what a contradictory relative quantum efficiency graph states that does not agree with other evidence and experiments such as cited at Reference #5).
We also need to understand that all these studies using different light spectrums for growth, including green, that these are in closed & controlled environments (which of course are aquariums are closed environments).
However in nature it has long been established, including in an episode of NOVA (PBS science series) that green light in the open environment of nature is generally not used.
So in the end, when one forces their plants or coral to utilize green light, we can make this analogy: "You ran out of your quality fish food, so instead you feed your fish soda crackers". While not a perfect analogy, it still makes a good point in that you are forcing the specimen whether it be a plant, coral, or fish to survive on less than optimal "nutrition""
www.aquarium-pond-answers.com/2012/03/pur-vs-par-in-aquarium-lighting.html#summary
Carl
Here is an excerpt:
"Summary
Hopefully readers come away after reading this article and its many cited resources with a better understanding of PUR/quality of light, not that I am stating certain LEDs or other lights in particular CANNOT keep photosynthetic life.
As well I am NOT stating that if a fixture uses green emitters it is a poor light.
In fact, green light has some proven applications in a closed environment for more growth when under 24% of overall light spectrum as well as producing a more pleasing overall light when part of the spectrum (as well as some synergy of all light spectrums). However a fixture that is heavier in the green spectrums is going to be less efficient for photosynthetic growth and possibly detrimental when over 25% of the overall spectrum as per cited .edu references.
I will also add that one has to look at the preponderance of evidence, both from .edu websites, NOVA, and similar sources as well as practical experiments and use COMMON SENSE that if one theoretical article comes to different conclusions, but the preponderance says otherwise, that we need to go with what in the end the majority of evidence states (not that what a contradictory relative quantum efficiency graph states that does not agree with other evidence and experiments such as cited at Reference #5).
We also need to understand that all these studies using different light spectrums for growth, including green, that these are in closed & controlled environments (which of course are aquariums are closed environments).
However in nature it has long been established, including in an episode of NOVA (PBS science series) that green light in the open environment of nature is generally not used.
So in the end, when one forces their plants or coral to utilize green light, we can make this analogy: "You ran out of your quality fish food, so instead you feed your fish soda crackers". While not a perfect analogy, it still makes a good point in that you are forcing the specimen whether it be a plant, coral, or fish to survive on less than optimal "nutrition""
www.aquarium-pond-answers.com/2012/03/pur-vs-par-in-aquarium-lighting.html#summary
Carl
