Study: Red light negatively affects health of stony coral

[koddyVT]

Pretty cool study, check it out:

http://www.advancedaquarist.com/blog/red-light-negatively-affects-health-of-stony-coral

 

[aguila88psi]

pretty cool

 

[Ted_C]

This - sir - is an awesome study. I really enjoyed reading the full version.
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092781#pone-0092781-g002

The only treatments that resulted in necrosis and/or mortality were those that included red light, either solely or combined with blue light. However, no adverse effect was found at a red irradiance of 64 μmol m−2 s−1 (blue red 128; Fig. 2), which suggests that red light may promote necrosis and mortality of S. pistillata at irradiance of 128 μmol m−2 s−1 and above

These guys thought of everything:

it is possible that the genotype used for this experiment was collected at a depth where red light is nearly or completely absent (<10 m) [8], rendering this coral sensitive to excess red light

Their control got messed up in week 6:

A caveat that has to be considered here is the necrosis of corals grown under the white light, which started during week 6. As this light spectrum is known to be suitable for aquaculture of this particular genotype [4], [17], this suggests that other factors than light may have caused necrosis and mortality at the end of the experiment.

Their conclusions about possible zinc concentrations, the narrow bandwidth blue light and the enhancing certain anti-oxidant qualities of Zooxanthlae are breathtaking.

 

[CrazyEyes]

That seems a little odd but I guess the proof is there. I just would have imagined red would have been more beneficial. If you look at the chlorophyll a chart there is a huge spike in 660nm (deep red). I wonder what red they were using for the experiment.

 

[Ted_C]

That seems a little odd but I guess the proof is there. I just would have imagined red would have been more beneficial. If you look at the chlorophyll a chart there is a huge spike in 660nm (deep red). I wonder what red they were using for the experiment.

Blue peaked at 452 nm

Red Peaked at 665 nm

The blue LED fixture (168 W) emitted a light spectrum with a peak at 452 nm (73 nm bandwidth) and the red LED fixture (120 W) showed a peak at 665 nm (74 nm bandwidth). The 50/50% blue red LED fixture (144 W) showed a combination of the blue and red spectra (Fig. 1). The T5 full spectrum control light exhibited various peaks across the visible spectrum. Most notably, the control light emitted a significant amount of blue light, with a blue to red ratio of approximately 3. A spectral analysis was conducted for each of the two irradiance intervals applied, which revealed that spectrum was not affected by irradiance level.