jeffm59
New member
Hey - could answer this for you at the swap tomorrow but
The short answer is yes - disclaimer - this is my opinion
For the long answer - there are quite a few scientific papers to show why a true full spectrum should result in better growth and color. This was a topic we covered in great detail at the last MARS meeting. After the presentation backed up with the research papers, graphs and charts, I believe everyone in the audience seemed to be understand that the science leans this way.
Do corals grow and have nice colors with a limited spectrum, yes - but I believe the same coral will have more growth and color under a full spectrum light. Taking it out of the LED world for an example, why do we all mix t5 bulbs, we are trying to provide a more complete spectrum for better growth and color.
With the great amount of work being done on the disappearance of the coral reef, science has now identified some 80 different strains of zooxanthellae that exist in marine animals such as coral, macro algae, clams and nems. The same strain of acropora when taken from different depths might have a different makeup of zooxanthellae in its tissues. Most of these zooxanthellae, use chlorophyll a as one of the major sources of photosynthesis. The two peak absorption wavelengths for chlorophyll a are around 430nm and hyper red 660nm. By providing LEDs that match these absorption peaks we should get better growth.
Aside from photosynthesis, there are also chromoproteins in the tissue of acropora which help in Photoprotection (UV) - Photo Regulation "“ Predator Protection. These proteins absorb one spectrum and emit another spectrum. The example we used in the presentation was for a red millie which contains a protein which absorbs the 590nm wavelength and emits color in the red 630nm spectrum. So for this millie to show the best color, it needs that 590nm to excite that protein and emit the red wavelengths, otherwise the red coloration of the coral might be lacking or dull. Here is just a small example of a part of table from an article in Advanced Aquarist showing some of the acros and the proteins they contain. Note that some of these proteins are absorbing wavelengths as low as 404nm UV and emitting light up in the 492nm (green/cyan) range. The psammocora I referencing from the chart below will show the best coloration only when provided with that 404nm spectrum.
We keep all our Zoas and Palys under a DIY full spectrum LED, after adding the 660nm reds and the true violets 405nm and 430nm, growth and color took off. It is a great experimental tank since the zoas grow faster and respond much quicker than sps to changes.
The colors in this tank really pop now, much more than they did under the same fixture without the supplemental colors being added. Today, I added the new 590nm ambers to the fixture and was pleasantly surprised. Some of the zoas now look completely different, small details in the skirts that you couldn't see before now show up with the addition of this small chunk of wavelength. Each new LED and its spectrum help fill in the missing pieces so that we can replicate natural sunlight on the reef.
LEDs have made giant leaps forward just in the last few months, and with the OEMs incorporating these changes into their fixtures it will be exciting to see what is going to develop.
