Open letter to the LED industry

[asid61]

I am not sure where you got the idea that MH won't bleach corals, rest assured you can certainly bleach, bake, fry and toast corals under MH and T5. :thumbsup:

I wasn't suggesting you can't either. You can bleach corals under PC lighting with enough power.
It's just that MH are not known for their bleaching effects on corals.

 

[zachts]

No, there's not enough chatter. I think that the reason we have aquarium MH lamps are because of horticulture- a thriving market for lights. Some 10k bulbs are even sold to provide more blue for plant growth. I am totally guessing here, but I think you could just adjust the gasses a bit to make it spit out more blue light.
As for heaters and pumps, both technologies are used in other applications like pools. Only the ascetics are bit different.

Leds are an entirely different matter. You have to mess with the different phosphors in a micro-area to produce different light and spectrums. It's an entirely different thing to do, versus simply putting in gas (which likely is not simple, but is in contrast with phosphors). Not to mention that the led companies would need to do some serious research on what phosphor blend to use- manpower that is hard to spare when you have competitors. The led market changes every year, and they have to keep up. How many reefers would buy such a chip? It would be huge gamble anyway due to the anti-led people.
Someday, we will probably end up with an aquarium-specialty led. But until then, we're stuck with multichips and dense matrixes.

I'm still convinced Remote phosphor will be the way LED lighting goes for reef tanks. seems to be much less complicated, almost simple by comparison to making a special reef LED chip. and if the user didn't like the color, they could just put on a different phosphor to the blue led arrays. Like changing out a t5 bulb.

 

[asid61]

Phosphors are microscopic. You can't just swap them out.

 

[nynick]

Phosphors are microscopic. You can't just swap them out.

Just google remote phosphor. Everything is microscopic if you make it small enough.

 

[senne76]

I actually have been looking at some videos of the triton s and the hyperion s , but also some videos of the triton r2 and the hyperion s and I do notice that there is much more disco ball effect with the s-series than with the r2-series . I actually like the r2 better, less discoball and more natural light (yes because of the white leds)

 

[asid61]

Just google remote phosphor. Everything is microscopic if you make it small enough.

Oh wow. I apologize zachts. I had no idea that kind of stuff existed.
In that case, we could come out with aquarium-specialty leds much sooner than I thought.

 

[Pacific Sun RD]

There is no disco effect(different colors on the sand) with SMT matrix - I dont have idea why it's looking so strong on that videos - maybe after fps conversion, I dont know.
When all leds are placed on 20mm square its not possible to have disco effect stronger that in panels where all leds are placed on big panel(large distances between the LEDs = big disco effect)

 

[Vannpytt]

It's a known problem in movie/tv and entertainment industry in general that LED runs on a frequency (Hertz) that in some cases displays when filming. The better the camera, the more of a problem. Same effect as using a camera on an old CRT screen or TV.

My field of work.

 

[jscarlata]

I actually have been looking at some videos of the triton s and the hyperion s , but also some videos of the triton r2 and the hyperion s and I do notice that there is much more disco ball effect with the s-series than with the r2-series . I actually like the r2 better, less discoball and more natural light (yes because of the white leds)

The videos are deceptive, it's not like that in person at all, the shimmer from the SMT triton s is superb, as is the color rendition...

 

[Pacific Sun RD]

Exactly, if you will see how close all leds are mounted(square 20x20mm) you will know that panel generate "shimmering" effect like metal halide..

 

[Zaita]

This chart is sun spectrum ABOVE water level(measured in Bali in our experiment trip at 2011 year)
If you will check which hard corals species live in shallow waters(up to 1.5m) you will see that there arent any with very nice colors and GFP pigments.
Allmost all strongly colored corals(coming from Acropora species) live below 5-10m(and deeper).

Have you done research in other places around the world? I've seen plenty of evidence that goes against what you've stated here.

I've seen many nice pink, purple, blue and green SPS species living in the top 2M of water with heaps of coloration, directly comparable to species living 10-25M. Even coral that is exposed for ~3hours of air during low-tide periods has good coloration.

For reference, first image @ ~10M and second image @ ~1.5M. Both taken inner reef Tonga 2013.
http://imgur.com/onuUZiz,bDVypxa,Zpyy7Bo,73sQ8Qx

 

[Bruce Leroy]

I dont have Coral+ spectrum reading here(in my home now) but I will show it to you on Monday.
Comparing Coral+ to Purple+ - they are VERY simillar - Coral+ have little stronger peak at green range and Purple+ have stronger peak at orange.
But spectrum area - is almost the same.
I founded poor quality "readings" - so we will compare it on Monday with real charts.

Still Looking for your Charts on the Coral Plus !

 

[Pacific Sun RD]

Have you done research in other places around the world? I've seen plenty of evidence that goes against what you've stated here.

I've seen many nice pink, purple, blue and green SPS species living in the top 2M of water with heaps of coloration, directly comparable to species living 10-25M. Even coral that is exposed for ~3hours of air during low-tide periods has good coloration.

For reference, first image @ ~10M and second image @ ~1.5M. Both taken inner reef Tonga 2013.
http://imgur.com/onuUZiz,bDVypxa,Zpyy7Bo,73sQ8Qx

Of course not - we hadn't dive in all places around world - I can only say that after our three long trips in Indonesia and Red Sea reefs.
Corals exposed to sun start produce slime to protect against drying and harmful effects of the sun.
Corals which you showed on the pictures have a DsRed pigments - visible in the warm color of light at shallow depths.
This is not a rule - but some principle which we have already seen.

 

[Zaita]

Of course not - we hadn't dive in all places around world - I can only say that after our three long trips in Indonesia and Red Sea reefs.
Corals exposed to sun start produce slime to protect against drying and harmful effects of the sun.
Corals which you showed on the pictures have a DsRed pigments - visible in the warm color of light at shallow depths.
This is not a rule - but some principle which we have already seen.

As I mentioned, I've seen many various bright colours at shallow depths (even in rock pools) in places like Tonga and Niue. The photos I posted the 10M one has strobe used to bring back the reds while the shallow one does not.

Tonga and Niue are good case study locations because they have very little human interaction with the reefs. Niue especially often has perfect water clarify with viz >40M because there is only limestone on the edges of the island.

I'm not saying your observations are incorrect, but perhaps there is more to the equation than has been considered. I'd be keen to see if someone has done some heavily profiling of coral health and colour across various pacific islands.

 

[PolyReef]

As I mentioned, I've seen many various bright colours at shallow depths (even in rock pools) in places like Tonga and Niue. The photos I posted the 10M one has strobe used to bring back the reds while the shallow one does not.

Tonga and Niue are good case study locations because they have very little human interaction with the reefs. Niue especially often has perfect water clarify with viz >40M because there is only limestone on the edges of the island.

I'm not saying your observations are incorrect, but perhaps there is more to the equation than has been considered. I'd be keen to see if someone has done some heavily profiling of coral health and colour across various pacific islands.

I did some research myself and I found it very interesting website
AIMS
Australia's tropical marine research agency

 

[Lassef]

Thank you Przemek for sharing your thoughts here. And a special thanks for an excellent thinking outside the box.

I totally understand the way you think because this issue with to much white light in the “lumen range“ were my major concern when we was discussing the “Dream Chip” in an other thread last year. My problem is that I like white light and do not want to see too much of the blue tint. However – 410 – 470 nm is essential for good photosynthesis for corals. The problem is to have so much of these wavelengths as possible without loosing other colours and make your eyes not to see how much of the blue wavelengths you are using .

The “Dream Chip” use white LED with high Kelvin rating (10 000 and 16 000) but for sure – it is still too much if you run them at 100 %. It is able mask much of the weaker emitting wavelengths in the orange/red region.

Your solution will give:

a good photosynthesis (the 410 – 470 nm range) and therefore a good growth.

not a lot of light in the “lumen window” and therefore not block your eyes to see weaker emitting colours from fluorescence

three RGB peaks so it will trick your brain that it is white light

supplementary wavelengths known for emitting photons in the orange/red region and you will see them because there is not much light in the “lumen window”

I’ll think that this is to use the LED technology the way it should be used


However (there is always a however ) as someone said before “is it not there – it is not there”. I think there are a lot of pigments reflecting wavelengths not present in your setup today. We also do not know everything about the biological influences of different wavelengths (hormone productions and so one)

There are also probably some pigments produced by corals that serve as antioxidants and their role are not known (or their colouration).

My personal believe is that the brownish colour you refer to as produced by to much of zooxanthellas in the tissue indeed is a sunscreen, not directly associated to the density of zooxanthellas.

One thing that you not mentioned is that a lot of the species that we call pest algae has adsorptions peaks for their photosynthesis in the “lumen window”

I think that the technology either will develop to more monochromatic LEDs in the matrix in order to fill up some of the gaps or that someone create a phosphorus layer that not has it maximum at the “Lumen window”.

By the way – to put 20 emitters in an area of 20*20mm are rather close to a multi chip or…..

Thank you again for sharing your thoughts (and that you revealing what is behind your design and why you chose not to use "white" LEDs) At least – it get me to use my brain again

I hope you understand what I mean with “Lumen window” – I mean the wavelengths that the human brain perceive to be the brightest

Sincerely Lasse

 

[Pacific Sun RD]

Hello Lasse,
Thank for your post - its very interesting and I see that you try to understand our point of view.
Of course, we analysed all possible(and discovered) pigments for excitation/emission charts and all other - like DsRed for reflection(not only that two charts showed by us in this thread)
In fact, if you will compare our SMT matrix spectrum chart you will see that there are "cut off" only lightwaves coming rfrom 540-570nm - all other lightwaves are emited..
For example please take a look for below pictures showing spectrum readings from other, good LED lamps(AI Hydra/GHL Mitras (we taken that pictures from their website).
These lamsp are also multichannel, they used white leds for build primary spectrum.

GHL Mitras

Hyperion SMT spectrum

First comparision Hydra/SMT - I tried to do two layers in picture with the same intensity peak for better/easier comparision(compared only 390nm-700nm range)

So - you can see important difference only in two areas - between 540-570nm (in our lamp that is very low - not 0, but low) and you can see other areas, where SMT matrix emit much more power - without affecting overal color(for our eyes). Red led is used only for better CRI and reflection of some red pigments.(not only red fluorescent - like discussed in must to read article written by Dana Riddle:
http://www.advancedaquarist.com/2007/2/aafeature
In that article you can see, there is not too many(if any) pigments with excitation range above 650nm(RedFlo pigments)
Also in that article:
http://www.advancedaquarist.com/2009/4/aafeature1
where discussed are DsRed pigments - also many corals "produce" visible red light after absorption of lightwaves coming from "left" side of visible spectrum(blue, green, yellow).
So - I want to remind it again - I never said that under white leds corals will not grow or they colors will be weak.
I only said, that maybe we found a way how to reach that "target"(nice colored and healthy corals) by using another method of build proper spectrum - with more light emission in some areas which was "forgotten" before..(compare 500nm spectrum peak in that waves range in SMT matrix and check how many pigments "need" that light to be visible and emit another colour of light..)
Also note how many people (that use LED lamps with white LEDs) use them for 20-30% - is not significant in this situation?
After reducing the power of white channel they note better coloration of corals - and if the "warm light" was responsible for the the best / strongest colors - would not it be the other way around?

I can agree that perfect would be developing led emitter which will work like tri-phospor T5 bulbs - we will can use diffrent layers and produce light "ready to use" with "pre-programmed spectrum - like 20KK MH with T5, like "the best" T5 combo etc..
I dont know - it will be possible or not - maybe es, but also I know the constraints imposed by the LED technology. But - who knows?

 

[senne76]

But a pink stylo utilises 560nm for their pink pigments as you mentioned in your charter, wouldn't it be smart to throw an 550-560nm led into the cluster?

 

[Pacific Sun RD]

pink styllo utilise not only that one pigment - but also two others, which have excitation peaks between 580 and 600).
Please remember - that for that pigment - 560nm is maximum "peak" in excitaion range...
For example - please take a look for below chart - pigment P484 in Acropora secale.
It have excitation range much wider than only 448nm.

 

[zachts]

Oh wow. I apologize zachts. I had no idea that kind of stuff existed.
In that case, we could come out with aquarium-specialty leds much sooner than I thought.

That was exactly my point.............