AliE LED bar vs. T5

[AKReefing]

Example of picking spectrum by flourescence..Note though the lower the blue the less it interferes with your eyes.

Hey, that's my diagram!

 

[AKReefing]

Just 470nm, or consider repeating 410/420/470. The G5/G6 went meh on the lower violet. The below is all channels at 100%.

Does not appear to be a huge difference in spectrum. Am I correct in thinking the primary differences are in the number of LEDs of each wavelength and total wattage for the three gens?

 

[AKReefing]

Just to fill the left side of the hr which peaks around 455-ish?
If the spectrum is correct adding something as simple as say 430:410 2:1.
Want to play the UV game say 400:410:430 1:1:2
Or skip the 410.
Of course each "color" will have it's own efficiency thus throwing off any way of actually balancing anything.
Just leaves sort of a best guess..

If you buy this action spectrum of one coral and one algae you see it peaks around 430 and diminishes in the 400 range.
Still effective but now in the same range as say cyan or green.
Of course there is always the discussion on the left side of 430 creating more "sunscreen" pigments than say boosting the right side (around cyan)
Then there is which band stimulates which florescent protein the best and also does not "glare" it out.

my less than 2 cents worth.

I think what is possibly being overlooked here is the action spectrum is only relevant if the amount of lumens being produced is significant enough to provide enough PPFD to make a difference. If you're only producing 50 lumens at 430nm, you may not be getting as much photosynthetic response as if you were producing 200 lumens at 450nm. In my experience, the higher wavelength LEDs are notoriously low in PPFD.

By "sunscreen" pigments, are you referring to the xanthrophylls, or to the carotenoids?

 

[AKReefing]

Here's your light running AB+ overlayed with Chl a (pink) and Chl b (yellow). You have 450nm covered (Chl b), and suggest not adding more. But then there's Chl a, and you're not hitting those peaks much at all. As you mentioned, a 410/420/470nm bar would compliment the G5 Radion quite well. The lower spectrum diodes would hit Chl a. The 470nm will give you some pop the Radion is lacking.

If it helps, here's a 425/440/470nm DIY version of the AliE bar that I ran with my G4 XR30. Those three were repeated along the length of the 24" bar. Totally stuck that thing in the oven and did some hot swapping. Yes...it's that easy.

Science stuff aside, you'll dig the added fluorescence of the 410/420nm. The G4 had that deep blue (415nm) that many users liked. And you know that biology band BRS mentions? That's PUR, and you'd be improving that quite a bit.

-Jim

Are you saying coral zooxanthellae have Chlorophyll b?

 

[telegraham]

Are you saying coral zooxanthellae have Chlorophyll b?

I was aligning the available spectrum with Chl peaks; however, this suggests that coral have Chl a. https://aslopubs.onlinelibrary.wiley.com/doi/pdf/10.4319/lo.1989.34.7.1331

 

[AKReefing]

I was aligning the available spectrum with Chl peaks; however, this suggests that coral have Chl a. https://aslopubs.onlinelibrary.wiley.com/doi/pdf/10.4319/lo.1989.34.7.1331

Ok, I see. Coral zooxanthellae do contain chlorophylls a and c2. Chlorophyll b is unique to land plants, algae and cyanobacteria. The reference you identified suggests the occurrence of chl b in the skeletons is endolithic--it exists within the coral skeleton where light is able to penetrate, perhaps as a hitchhiker, independent of the living coral tissue and zooxanthellae, and plays no role in coral nutrient production.

 

[AKReefing]

BTW, I'm enjoying your YT videos.

 

[oreo54]

I think what is possibly being overlooked here is the action spectrum is only relevant if the amount of lumens being produced is significant enough to provide enough PPFD to make a difference. If you're only producing 50 lumens at 430nm, you may not be getting as much photosynthetic response as if you were producing 200 lumens at 450nm. In my experience, the higher wavelength LEDs are notoriously low in PPFD.

Actually since lumens is a subset of PPF
And Lux is Lumens/area like PPFD.
1000 Lux of 450nm blue = 115 PPFD
1000 Lux of "daylight" is 23 PPFD

Convert Lux to PPFD - Online Calculator | Waveform Lighting

Online calculator to convert illuminance (lux) to PPFD (micromoles per second per meter squared).

www.waveformlighting.com

Lux/Lumens really have little use here.

By "sunscreen" pigments, are you referring to the xanthrophylls, or to the carotenoids?

Doesn't matter, those or Maa's ect. Whichever are being produced in response to whatever wavelengths.

Hey, that's my diagram!

You are Dan Kelly?

Chinese black box LED

I appreciate your sense of humor! I started a thread about fires started by black boxes and asked for experiences and photos. There were several responses stating the boxes were smoking, but no photos of burned boxes. Smoke doesn't necessarily mean fire as a a resistor or LED going south can...

www.reef2reef.com

 

[telegraham]

Ok, I see. Coral zooxanthellae do contain chlorophylls an and c2. Chlorophyll b is unique to land plants, algae and cyanobacteria. The reference you identified suggests the occurrence of chl b in the skeletons is endolithic--it exists within the coral skeleton where light is able to penetrate, perhaps as a hitchhiker, independent of the living coral tissue and zooxanthellae, and plays no role in coral nutrient production.

Which begs my ignorance-based question…why are most all LED reef lights firing 450nm down range? Availability at the time of introduction, and the hobby has just stuck with it? I’m looking at a 14,000k MH, and it peaks at ~420nm. I think the only LED I’ve tested with an all channels at 100% peak around 420nm was the original ReeFi Uno. Is it the Carotenoids bump that’s shown in some charts as being a touch lower than 450nm?

 

[oreo54]

Which begs my ignorance-based question…why are most all LED reef lights firing 450nm down range? Availability at the time of introduction, and the hobby has just stuck with it? I’m looking at a 14,000k MH, and it peaks at ~420nm. I think the only LED I’ve tested with an all channels at 100% peak around 420nm was the original ReeFi Uno. Is it the Carotenoids bump that’s shown in some charts as being a touch lower than 450nm?

Royal blue were the most available, most efficient and at the beginning " cheapest" LEDs one could get.

Besides gave great " pop".
Actually still holds true today mostly.

Zoo light harvesting when factoring in the efficient PCP complex is quite broad.

Peridinin-chlorophyll-protein complex - Wikipedia

en.wikipedia.org

Peridinin outnumbers chl a in, usually, a 4:1 ratio and has close to 100% energy transfer into the photo system.

 

[telegraham]

Royal blue were the most available, most efficient and at the beginning " cheapest" LEDs one could get.

Besides gave great " pop".
Actually still holds true today mostly.

Zoo light harvesting when factoring in the efficient PCP complex is quite broad.

Peridinin-chlorophyll-protein complex - Wikipedia

en.wikipedia.org

Peridinin outnumbers chl a in, usually, a 4:1 ratio and has close to 100% energy transfer into the photo system.

I prefer the pop from 470nm, which is why the AliE bars are such a value.

 

[oreo54]

I prefer the pop from 470nm, which is why the AliE bars are such a value.

Yea but 450/470 vs anything else...
470 starts to impact peoples "windex alert"...

But yea, 470 is more of the sweet spot but if factoring in overall psychological preference (what is wrong with windex?) it loses out.

Not to mention your sensitivity to the blue increases thus adding a bit more blue glare at 470-ish.
Under "low light" conditions your eye is almost 2x more sensitive to 470 than 450.
I'd consider most aquariums as low light certainly as compared to 1700 PPFD daylight.
Yea a choice.

Keep in mind the excitation nm (bell curve-ish, not single point. These are just peak wavelength points. Ignore any that show emission at lower nm than excitation nm. You can't generally "excite" at 500nm and "emit" at 480nm) 470 hits more pigments.

 

[AKReefing]

Which begs my ignorance-based question…why are most all LED reef lights firing 450nm down range? Availability at the time of introduction, and the hobby has just stuck with it? I’m looking at a 14,000k MH, and it peaks at ~420nm. I think the only LED I’ve tested with an all channels at 100% peak around 420nm was the original ReeFi Uno. Is it the Carotenoids bump that’s shown in some charts as being a touch lower than 450nm?

Here's my long-winded opinion/answer (the shortened version, lol). Since well over a decade ago ~450nm royal blue and ~465nm blue LEDs were the only blues commonly available. That's when reefers started experimenting with them. We've learned to appreciate the combination of growth, coloration and fluorescence associated with them. Reefers like the visual pop, so manufacturers throw together what's readily available and cheap, and consumers love them. There's no valid need for additional shades of blue or violet, which would require effort on the part of the semiconductor manufacturers, so that's what were still getting. The wavelength variations we're seeing are a result in variability during manufacturing, resulting in post-production binning.

The "bump" really only has to do with where photosynthesis is most efficient and not where more absorption occurs. Focusing on 420nm doesn't guarantee you'll get the best growth, primarily because 420nm LEDs really don't have a tremendous lumen output. You'd need a ton of them, and you'd miss out on the visual benefits of a broader blue spectrum. The antenna pigments and the PCP complex are very effective at capturing photons from below 400 to above 500nm, and making all of that energy available for photosynthesis. I'm sure there are many articles by Dana Riddle that explain in detail.

As with LEDs, halides use a finite set of ingredients--mercury, argon, xenon, and halides (generally iodides)--and various ratios of each, so the peak emissions are based on which materials are used, and how much. That would be Dr. Sanjay's area of expertise.

I'm not "the" expert. I've learned a lot from the people who are experts.

 

[oreo54]

Only thing that really matters is the number of photons produced per unit of energy applied..
Blues (inc UV/violets. Same goes for the red side) are generally measured in mW of output due to the fact lumens just don't apply here.
Even that measurement isn't perfect since a photon of say 400nm light actually contains more energy than a photon of 470nm. 1mW of 400nm has less photons than 1mW of 470nm assuming equal efficiency.
Which isn't the case.
Photon energy: E(typically joules) = hf
1 Watt = 1 Joule per second
Point is it gets sort of messy and not necessarily needs to be a concern since you will basically go on "par"
(depending on definition 400-700nm) or PPFD for the most part.
Funny, you put in electrons to kick photons out and then you count electrons generated by photons to give you the number of them. Circle of life.

Thus everything needs to be measured on the quantum level.. # of photons to compare.

Yes generally speaking you have less photons generated out of a 420nm led than a 470nm led when run at the same err wattage.

But you definitely don't need buckets full of them to equal. Maybe 3:1 in some of the worst cases. Just a guess.
Based on some of the last known numbers on efficacy like 70% vs 45%.

Now some UV's are like 10% so yea.. buckets but most of those are out of the photosynthetic range.
Anyone have any real data over my "historical memory" it would be appreciated.
I will be looking through this since using a violet pump is somewhat equiv to a violet led.
violetpumpled
They have a different goal though.



Sadly nobody has applied the violet/phosphor thing for reef centric leds.
Well except Kyocera.

Though def less overall efficiency they are err "usable" meaning they can't be all that bad.
Since these are pc converted to white yea one can use lumens.

The luminous efficacy of the violet-pump LEDs examined during this study was generally lower than
that excepted from typical blue-pump phosphor-converted LEDs (pcLEDs). Although the violet LEDs
were found to be stable in the AST conditions, the stability of the phosphors used in the violet-pump
LEDs varied greatly, resulting in significant changes in luminous flux and chromaticity in some
conditions

 

[AKReefing]

Only thing that really matters is the number of photons produced per unit of energy applied..

In regards to PPFD? Ok, but reefers have more in mind than that.

Yes generally speaking you have less photons generated out of a 420nm led than a 470nm led when run at the same err wattage. But you definitely don't need buckets full of them to equal. Maybe 3:1 in some of the worst cases. Just a guess. Based on some of the last known numbers on efficacy like 70% vs 45%.

I think you dashed down a rabbit trail over that one. The real point I was making was that there's no need to be concerned about the 420nm peak in the photosynthetic response curve.

 

[AKReefing]

Which begs my ignorance-based question…why are most all LED reef lights firing 450nm down range? Availability at the time of introduction, and the hobby has just stuck with it?

When I was just starting out in LEDs only blue (~470) and royal blue (~450) were available, and I believe they're still the most commonly available blues out there. Ask ChatGPT, "Why was 450nm chosen when making blue LEDs?" Then ask the same question for 470nm. It gives a number of good reasons why 450 and 470 may have been chosen.

 

[Nonya]

Disregard

 

[Nonya]

Dup

 

[Nonya]

Want to play the UV game say 400:410:430 1:1:2

UV starts at 400nm?

 

[Royal_pudding]

UV starts at 400nm?

My understanding is anything 400nm and above is not UV.