Post About Wasteful Spectrum in LEDs

[Dana Riddle]

I took a Kessil 360, Gen 3 Radion, 14K Phoneix and 20K Radium (both run on M80) to use an integrating sphere at the Engineering School at the Alma Mater since I cannot afford one to just keep around the home - I mostly wanted to know the radiated watts of each vs the wall-power. The output in radiated watts of the 20K radium over 720nm was 2% of the total. The Phoenix was a bit more at like 3%. Both of the panels were about .4-.5%. The sphere was only 36", so we did not test any T5s.

I'm so dense... You took various light sources and put them in an integrating sphere and measured output with a spectroradiometer over a bandwidth of 720nm and found the UV output to be 2% *or* radiation at 720nm to 2000nm was 2% of the total. Or???

 

[jda]

The question is kinda hard, but is there a way to determine if the peaks in diodes are wasted? Is running a fixture with too many of a certain type of diode just throwing wattage away? I truly believe from my own experiences and eyes that there are no efficiences in a reef tank for any certain kind of light and that 70W of LED will provide the same results as a 70W MH (let's take spectrum out of this), but I cannot quantify this. I can throw away stuff like LUX and PAR meters which have enough problems that we all know about, but there is something else there that I don't understand about all of this. I think that I fully understand that white diodes have harmful radiation since they harm corals at higher output levels, yet I could thrown on a few more 5.5K MH would make them thrive. Do blue diodes do a similar thing where they don't harm coral, but they also waste energy? Sorry for my stupidity.

We got just over 73 radiated watts from a 20K Radium on M80 ballast with output capture capped at 720nm. In the whole range (wide open), we got just under 75 watts (73.2 vs 74.8). About 2% more. You are not dense (I imagine that you know this, but thanks for taking it easy on me)... I am just not good with the jargon.

BTW - the next time that somebody wants to do a study, please have them give me a few months notice and I can have a few dozen acropora frags ready to ship. I am kinda sick of Pavona, Porites, Montis and other studies with stuff that I have grown in my fuge under incandescent lights.

 

[Dana Riddle]

The question is kinda hard, but is there a way to determine if the peaks in diodes are wasted? Is running a fixture with too many of a certain type of diode just throwing wattage away? I truly believe from my own experiences and eyes that there are no efficiences in a reef tank for any certain kind of light and that 70W of LED will provide the same results as a 70W MH (let's take spectrum out of this), but I cannot quantify this. I can throw away stuff like LUX and PAR meters which have enough problems that we all know about, but there is something else there that I don't understand about all of this. I think that I fully understand that white diodes have harmful radiation since they harm corals at higher output levels, yet I could thrown on a few more 5.5K MH would make them thrive. Do blue diodes do a similar thing where they don't harm coral, but they also waste energy? Sorry for my stupidity.

We got just over 73 radiated watts from a 20K Radium on M80 ballast with output capture capped at 720nm. In the whole range (wide open), we got just under 75 watts (73.2 vs 74.8). About 2% more. You are not dense (I imagine that you know this, but thanks for taking it easy on me)... I am just not good with the jargon.

BTW - the next time that somebody wants to do a study, please have them give me a few months notice and I can have a few dozen acropora frags ready to ship. I am kinda sick of Pavona, Porites, Montis and other studies with stuff that I have grown in my fuge under incandescent lights.

 

[Dana Riddle]

No, no. I think you were easy on ME, and I hope I'm not preaching to the choir... There is probably a way to judge wavelength issues using a monochromator and a PAM fluorometer IF we can figure out to overcome problems with the Emerson Effect (irradiating with blue or red light in separate experiments might do it if calibration challenges can be resolved.) I shudder at the thought. A PAM, a monochromator, and a spectroradiometer *might* work. @saltyfilmfolks - here's a project for you in your spare time. JK.

 

[Dana Riddle]

The question is kinda hard, but is there a way to determine if the peaks in diodes are wasted? Is running a fixture with too many of a certain type of diode just throwing wattage away? I truly believe from my own experiences and eyes that there are no efficiences in a reef tank for any certain kind of light and that 70W of LED will provide the same results as a 70W MH (let's take spectrum out of this), but I cannot quantify this. I can throw away stuff like LUX and PAR meters which have enough problems that we all know about, but there is something else there that I don't understand about all of this. I think that I fully understand that white diodes have harmful radiation since they harm corals at higher output levels, yet I could thrown on a few more 5.5K MH would make them thrive. Do blue diodes do a similar thing where they don't harm coral, but they also waste energy? Sorry for my stupidity.

We got just over 73 radiated watts from a 20K Radium on M80 ballast with output capture capped at 720nm. In the whole range (wide open), we got just under 75 watts (73.2 vs 74.8). About 2% more. You are not dense (I imagine that you know this, but thanks for taking it easy on me)... I am just not good with the jargon.

BTW - the next time that somebody wants to do a study, please have them give me a few months notice and I can have a few dozen acropora frags ready to ship. I am kinda sick of Pavona, Porites, Montis and other studies with stuff that I have grown in my fuge under incandescent lights.

 

[Ryan115]

So I guess to broaden the topic of wasteful spectra, can anyone explain why Orphek added 850nm emitters to the Atlantik V4?
The only reason I can think of is so that they can say they have the widest spectrum of any fixture on the market.

 

[Dana Riddle]

Corals grown under incandescent lights... I took some heat when I suggested in my mid-90's book that this was possible if intensity and heat weren't issues. Glad to hear someone actually did it. I will take you up on your offer of Acropora specimens. My lab is still a work in progress with some electrical work to be done, and shelves installed, and so on. The microscopes took a beating during shipment, the most expensive single instrument I own (~$5,000) took some coaxing to become operational again, the NIST UV radiometer and sensors are missing, and so on, but the lab is becoming functional. Plus I'm recently retired and it operates on a shoestring budget... I'm PM you later. Thanks for the offer!

 

[Dana Riddle]

So I guess to broaden the topic of wasteful spectra, can anyone explain why Orphek added 850nm emitters to the Atlantik V4?
The only reason I can think of is so that they can say they have the widest spectrum of any fixture on the market.

Far Red light is known to relax pressure on Photosystem II. Ronny Schopke (sp?) sent me some fluorometer data that seems to confirm this. My Atlantik V4 will be here Friday. More later.

 

[jda]

I can totally assure you that Montis and Porites will grow under 100W daylight bulb that I was also using to grow chaeto. You can bet that the water parameters were very good since it was attached to my main tank. I did not put incandescents over my tank or anything, just in the fuge, but they grew and encrusted up the sides.

I will be happy to help with frags and stuff... just need time for them to heal. I can get many of the same ones if that helps with control.

Thanks for the responses and effort - I will just go on supposing for now that I am accurate about no real efficiences and await more stuff.

 

[Ryan115]

Far Red light is known to relax pressure on Photosystem II. Ronny Schopke (sp?) sent me some fluorometer data that seems to confirm this. My Atlantik V4 will be here Friday. More later.

I think I must have missed that section in Bio-chem.
So realistically what sort of penetration depth could you get out those emitters?

 

[Dana Riddle]

I think I must have missed that section in Bio-chem.
So realistically what sort of penetration depth could you get out those emitters?

The Walz PAM fluorometers use Far Red radiation after the saturation pulse in order to drain off any traffic jam of electrons between PSII and PSI - this is spelled out clearly in their operations manual with references to Max Planck. But your question is an excellent one - how is PSII relaxed in the ocean under conditions of high light intensity if this Far Red radiation doesn't penetrate, or if the coral is in a, or creates its own, shadow? Is it possible that state transitions ('spillover' from Photosystem II to PSI) is the pressure relief valve? If not, then what? You can bet that I'll look at the Atlantik V4 closely with every instrument I have (PAM fluorometer, Ocean Optics fiber optic spectrometer, and OptiSciences chlorophyll meter.) Some Germans got pretty excited when we discussed the possibility of positive effects of Far Red radiation, and they pursued it, finding proof they claim to be beneficial (I'm not discounting their claims, as there is other evidence. I just want to see it for myself in different corals.)

 

[Hans-Werner]

PUR and some other assumptions done on green plants are not as helpful in corals and other than green algae. Zooxanthellae are brown because reddish carotenoids are their main antenna pigments. Together with green chlorophylls it results in a brown color. This means zooxanthellae and brown algae absorb much more blue light for photosynthesis than green plants and in this way their specific PUR is quite different from the PUR of green plants.

The other thing is that blue light controls the adaptation of algae to light intensity via Cryptochrome/Blue Light Syndrome (other algae use the light adaptation via Phytochrome red/far red like green algae). I think the exact consequences of blue light of high intensity to the light adaptation of corals is not well understood yet. I think this might also be a key to understand how corals adapt PSII and PSI to light intensity. I suspect that narrow bandwidth blue light of high intensity leads to a maladaptation of zooxanthelae to light intensity by reduction of photosynthetic pigments and driving down photosynthesis.

 

[mcarroll]

Dana, can you explain this "pressure release" that you've mentioned? I haven't run across the term yet, so I'm not sure what you're referring to. Does it show up here: http://plantphys.info/plant_physiology/light.shtml

 

[Dana Riddle]

Dana, can you explain this "pressure release" that you've mentioned? I haven't run across the term yet, so I'm not sure what you're referring to. Does it show up here: http://plantphys.info/plant_physiology/light.shtml

"Pressure release" is a decidedly non-scientific term used to describe a flow increase of electrons from Photosystem II to Photosystem I. If this flow of electrons 'backs up' in Photosystem II, damage (or destruction) of the PSII apparatus can result. I picked this term up in a Science article a few years ago that described the Xanthophyll Cycle as a 'pressure relief valve' for photosynthesis when there is a lot of light.

 

[oreo54]

So I guess to broaden the topic of wasteful spectra, can anyone explain why Orphek added 850nm emitters to the Atlantik V4?
The only reason I can think of is so that they can say they have the widest spectrum of any fixture on the market.

There are "reasons" for adding >700nm light to things.. but can't see what that band or the implementation (should be it's own channel) is..

HOW PLANTS USE FAR RED: Between 710 and 850nm we have Far-red light, which plants are sensitive to as well. Far-red does less to drive photosynthesis, but can greatly effect plant development or morphology. For example, certain ratios of red to far-red can tell plants that they’re under a canopy of taller plants, triggering them to grow taller in response. This is referred to as a shade avoidance response.

also has some influence on red algae...though never looked at it too deeply.

 

[mcarroll]

"Pressure release" is a decidedly non-scientific term used to describe a flow increase of electrons from Photosystem II to Photosystem I. If this flow of electrons 'backs up' in Photosystem II, damage (or destruction) of the PSII apparatus can result. I picked this term up in a Science article a few years ago that described the Xanthophyll Cycle as a 'pressure relief valve' for photosynthesis when there is a lot of light.

Dig it!

I think that is more or less illustrated in this section on the plantphys link:

Red and Far-Red Light are Synergistic
Emerson also tried combining wavelengths and observed that red light (680 nm) could drive a certain amount of photosynthesis; far-red light (700 nm) could drive a similar amount. When the two colors of light were combined, the amount of photosynthesis yield was greater than the sum of the individual color yields:

This was called the Emerson enhancement effect and was the first good evidence that there were two photosystems, that one absorbed red light and the other absorbed far-red light, and that they both must operate to drive photosynthesis most effectively.

The Light Reactions are an Energy Transfer system
Using the information of Emerson, and further evidence since then, the basic photosystems for photosynthesis can be diagrammed. The need for two systems is explained when the system's energy is plotted on a vertical redox potential axis. Redox potentials that are oxidizing are at the bottom and those that are reducing are at the top. The light reactions of photosynthesis have often been sketched in the form of what is often called the Z scheme. I know it looks more like an N scheme...and here we emphasize the pigments and the light. In this particular sketch, the electron transfer system in the middle of the diagram has been omitted (more on that later!).

I really cannot tell you why we still call it a Z scheme when it looks like an N in most diagrams (as in the one above)...except that it was originally drawn sideways. What you should notice for now, is that the red-driven (680 nm) photosystem (PSII) and the far-red-driven (700 nm) photosystem (PSI) cooperate to transfer electrons from the photolysis of water to a B-vitamin known as NADP+.

Thinking of this system, you can see that an electron is excited by light energy absorption in a P680 chlorophyll, a reaction center pigment in PSII. This electron is passed through an electron transfer to PSI. The electron lost is replaced by the photolysis of water. This reaction is sometimes called the Hill reaction in honor of Robin Hill who studied it. Photolysis of water is the source of the oxygen produced in photosynthesis. The electron that left PSII and passed through the electron transfer system replaces an electron that is lost by PSI after it is excited by 700 nm light energy. This electron is ultimately trapped with an accompanying proton onto NADP+, a high-energy vitamin B molecule. You should also notice that PSI is not a strong enough oxidant to draw electrons from photolysis of water, and that the energized PSII is not a strong enough reductant to donate electrons to NADP+. Thus, both photosystems are needed to both oxidize water and to reduce NADP+...this explains why Emerson observed the (red/far-red) enhancement effect.

 

[mcarroll]

Are you thinking we're lacking (enough) 700nm Red to keep the two systems active/balanced under some circumstances? (Interesting idea, if so.)

 

[mcarroll]

Looking for the "pressure relief" (not done looking) I found http://www.advancedaquarist.com/blog/2014/5/aafeature where you tested reds, but only 631nm and 657nm.....have you looked at 680nm and 700nm before?

 

[saltyfilmfolks]

work. @saltyfilmfolks - here's a project for you in your spare time. JK.

Sounds good Dana. I'll see what's in the garage to build one.

 

[oreo54]

850nm is more of the question though.. Technically "off the chart" for P(r)/P(fr) effects in higher photosynthetic organisms. Does seem to play out a bit on red algae and and some bacteria:
http://photobiology.info/Jones.html

Pigments. The main light harvesting pigment in purple photosynthetic bacteria is not chlorophyll but bacteriochlorophyll (BChl), a closely related magnesium porphyrin that has a more saturated tetrapyrrole ring (Figure 1A). This causes BChl to absorb at significantly longer wavelengths than chlorophyll in the near infrared, the absorbance spectrum being dictated by the details of the conjugated

electron system of the macrocycle (Blankenship, 2002) (Figure 1A). Light harvesting is also carried out by a variety of carotenoids that provide the main pigmentation in the visible region of the spectrum, and so make purple bacteria purple (or a variety of other colours).

Have no clue why this would be "useful" though...