Open letter to the LED industry

[mhucasey]

The eveness verses the sparkle is something that is debatable. People that loved the MH's and went to T--5's missed it others do not like it. I personalty like a little sparkle that you do not get with t-5's. So to me using more slightly higher powered LEDS is the key to get some sparkle.

As far longer LED life yes but I have run CREEE LEDs 15% over there maximum rating for 4 years now without any issues. However on several unknown brand Violet LED's even running them at there rated current produced issues in less than 6 months.

As far as the warm whites yes you did not mention them. However on another board they were mentioned on a Dutch LED system that used 16 Warm Whites, 16 Cool Whites and 16 Royal Blues. Sorry if I got the two confused. But they also offered a premium system that added 8 Violets, 8 True Blues, 4 reds, and 4 deep reds. The basic system ran the LED's at 350ma and the premium ran them all at 500 ma. They claimed the basic system was 50 watts and the advances was 120 Watts.

No worries, I just wanted to make sure we were both on the same page. There are a lot of LED systems in Europe as I'm coming to find out, and like just about everything in this hobby, they are ahead of us.

It is interesting how many of the systems there have a stated goal of replicating T5s, where here in the US we try to replicate Metal Halide. In many of the threads I read, there was a distinct dislike for shimmer, especially extreme shimmer. Quite a few I saw referred to Kessils as "Strobe lights":lolspin:

I'm one of the people who doesn't miss the shimmer, I find it hard to focus on the corals when it is especially strong.

 

[mussel and hate]

The Lani pro is interesting. I attempted a similar effect on my DIY with 54 stars on a 12" Makers HS dimmed down on 450ma drivers. I'm not sold on the red yet but I like the spread from many low current emitters.

Dennis were the problems you encountered with 430nm emitters due to burned lenses or did the diodes themselves fail? Also were these the large die package or the newer ones with the X-TE footprint? I have both types and observed lens failure on the older variety though after lens removal they continue to operate.

 

[TropTrea]

The Lani pro is interesting. I attempted a similar effect on my DIY with 54 stars on a 12" Makers HS dimmed down on 450ma drivers. I'm not sold on the red yet but I like the spread from many low current emitters.

I did a little computer generation of the spectrum that the Lani Pro combination and the combination I like to use and found that they are not as far apart as I realized. The big difference I think is that I use mainly neutrals for whites which picks up the red end of the spectrum more than cool whites do. On the Blue end I get a little more of peak in the 420 range since I use 410-420 nm LED's and they we think they are using 430's. But I do have a dip in the 435 area that is not as predominate in theirs.

Dennis were the problems you encountered with 430nm emitters due to burned lenses or did the diodes themselves fail? Also were these the large die package or the newer ones with the X-TE footprint? I have both types and observed lens failure on the older variety though after lens removal they continue to operate.

Yes the ones I had were much larger die than the standard Cree LEds XPE, XTE, XPG, XML, or the newer 2's. Yes the lens is what browned out for me after time to the point where there was barely any visible light there at all. No Im not talking about the lenses some people add to there stars to focus the bean but the lens actually designed to protect the actual junction. I do not believe this lens can be removed but I might be wrong on that.

I got those 430 nm LED's in Dec of 2011 and again in June of 2012 with the second batch I tried running at 350 ma and had the same issue. Only difference is they did last longer at the lower current.

Interestingly I also bought 410nm LED's at the same time I bought the 430 from a different source. I have not had one fail and even though they are recommended to run at 700ma max I have 4 running at 1040 ma for over a year without any issues.

 

[TropTrea]

No worries, I just wanted to make sure we were both on the same page. There are a lot of LED systems in Europe as I'm coming to find out, and like just about everything in this hobby, they are ahead of us.

It is interesting how many of the systems there have a stated goal of replicating T5s, where here in the US we try to replicate Metal Halide. In many of the threads I read, there was a distinct dislike for shimmer, especially extreme shimmer. Quite a few I saw referred to Kessils as "Strobe lights":lolspin:

I'm one of the people who doesn't miss the shimmer, I find it hard to focus on the corals when it is especially strong.

I never had an issue with excessive shimmer with my LED's. However I ususally run 3 to 4 lines of them the length of the tank with a spacing of between 3 and 4 inches. So on a 120 gallon tank 48" X 24"X24 " I'm running 36 to 64 LED's dependent on the current I'm running them at. On some I took the front row of LED's and actually angled them to add some shimmer to the tank. However unlike many people I do not run any lenses on my LED's which allows the different colors to blend together much easier.

No I do not have the shimmer I had with Metal Hides or the sharp shadows. But I also do not have quite the evenness that I had with T-5's either. If I ran 64 LED's all at 700ma or less there probably would be close to what you get with T-5's as far as evenness.

 

[zachts]

I got those 430 nm LED's in Dec of 2011 and again in June of 2012 with the second batch I tried running at 350 ma and had the same issue. Only difference is they did last longer at the lower current.

Interestingly I also bought 410nm LED's at the same time I bought the 430 from a different source. I have not had one fail and even though they are recommended to run at 700ma max I have 4 running at 1040 ma for over a year without any issues.

Try Cutter Electronics they seem to stock the same model chips in 430nm that RapidLED sells. A bit pricier but I'd be willing to bet they last. I'll be ordering some for my next project some time this spring likely.

You can pop the lens off of the large button style LED chips, I've done it premtively to some that I knew were going to end up burning just to confirm that it was due to cheap plastic not heat. with dome poped off the soft silicone below caught a few bugs from time to time but the leds stayed bright and strong over a year, where as the domes would have burned up 4 times in that period.

Unfortunatly even the 430nm chips in the smaller square footprint available in the states for the hobby are still using inferior plastic. My last test batch I need to power down and take a closer look at but I'm pretty sure they are burning up. I just can't see clearly with secondary lenses on them at the moment.

The luxeon z that are now slowly hitting the market give me hope!!

 

[mussel and hate]

You can pop the lens off of the large button style LED chips, I've done it premtively to some that I knew were going to end up burning just to confirm that it was due to cheap plastic not heat. with dome poped off the soft silicone below caught a few bugs from time to time but the leds stayed bright and strong over a year, where as the domes would have burned up 4 times in that period

I did this also. Just grip the primary lens with some pliers and pull straight away from the substrate, It'll pop off clean if your lucky. I run a splash guard so mine have remained pretty clean.

Unfortunatly even the 430nm chips in the smaller square footprint available in the states for the hobby are still using inferior plastic. My last test batch I need to power down and take a closer look at but I'm pretty sure they are burning up. I just can't see clearly with secondary lenses on them at the moment.

You just made me feel trepidation at the prospect of my replacements failing. I sure hope mine fair better.

 

[TropTrea]

Would love to see something like the Philips LHUV-0425 available from somebody in a star mount. While I'm not a Phillips fan compared to CREE I do see a lot of possible potential in this line according to the Phillips data sheet. Unfortunately they do show the band width on this LED though.

 

[Fredfish]

Try Cutter Electronics they seem to stock the same model chips in 430nm that RapidLED sells. A bit pricier but I'd be willing to bet they last. ...

Why do you think these will last where all the others have not? Does Cutter use different lenses?

 

[trueperc]

I have to say I have enjoyed reading this thread. I really hope the led manufactors are reading this. What do you thing about this red leds being harmful:

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

 

[nynick]

I have to say I have enjoyed reading this thread. I really hope the led manufactors are reading this. What do you thing about this red leds being harmful:

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

It doesn't say that red lights are harmful.

It claims that (some?) corals adjust their light intake based on the amount of red light of a certain spectrum they receive.

 

[conix67]

Well, what do you guys think of this - http://www.advancedaquarist.com/blog/red-light-negatively-affects-health-of-stony-coral

 

[nynick]

Well, what do you guys think of this - http://www.advancedaquarist.com/blog/red-light-negatively-affects-health-of-stony-coral

I would say that I think pretty much the same thing about that too....given that it is the same article.

 

[mhucasey]

It doesn't say that red lights are harmful.

It claims that (some?) corals adjust their light intake based on the amount of red light of a certain spectrum they receive.

Actually it does say that red light is harmful if the qty in relation to blue light is too great:
"Overall, our results suggest that red light negatively affects the health, survival, symbiont density and NDVI of S. pistillata, with a dominance of red over blue light for NDVI"
Obviously it is yet another study using Stylophora Pistillata, which in my experience is pretty much an unkillable weed, but in their study the red light burned the tissue right off the coral. My intuition tells me that acroporas would do worse in the same experimental setup.

I farmed a bunch of purple stylo frags a while back and traded them to my LFS for credit. They use Radions exclusively, and I came back a week later to find the tips of many of the stylo frags were burned in a similar fashion. Interesting in light of this study.

 

[conix67]

I would say that I think pretty much the same thing about that too....given that it is the same article.

Sorry, I missed the post

 

[Fredfish]

It doesn't say that red lights are harmful.

It claims that (some?) corals adjust their light intake based on the amount of red light of a certain spectrum they receive.

"However, it is still unclear whether these physiological processes are blue-enhanced or red-repressed"

"Note: red light is commonly found in proven lights such as Radium metal halides and numerous fluorescent bulbs as well as in wild reefs, so the idea is not that red light is necessarily harmful but that too much red light can have negative effects on how stony corals regulate photosynthesis."

"Overall, our results suggest that red light negatively affects the health, survival, symbiont density and NDVI of S. pistillata, with a dominance of red over blue lightfor NDVI "

It would appear that the hypothesis is that some processes within the coral are driven by the amount of red light rather than blue. It is not clear from the summary article, but it appears that the author thinks this applies more generally to corals, not just one or some species. Interesting stuff.

I would love to get my hands on the full paper to see what red spectrum was used.

It is difficult to say what the implications are in aquariums without knowing what spectrum is involved and what the absolute levels of those specra are before harm results. All red is obviously very bad, but I doubt that anyone has near those levels of red in their LED lighting.

 

[nynick]

From the article I must say that it doesn't seem that it will have too much effect on anything other than a little fine tuning for some led setups. Not much to be done for T5 or MH and most LEDs tend to be heavy on the blue anyway.

It is an interesting read though.

 

[zachts]

You just made me feel trepidation at the prospect of my replacements failing. I sure hope mine fair better.

If they were from that site that we can't talk about then I don't have high hopes. I was skeptical from the start as the chips lenses appear slightly cloudy from the get go........

 

[TropTrea]

"However, it is still unclear whether these physiological processes are blue-enhanced or red-repressed"

"Note: red light is commonly found in proven lights such as Radium metal halides and numerous fluorescent bulbs as well as in wild reefs, so the idea is not that red light is necessarily harmful but that too much red light can have negative effects on how stony corals regulate photosynthesis."

"Overall, our results suggest that red light negatively affects the health, survival, symbiont density and NDVI of S. pistillata, with a dominance of red over blue lightfor NDVI "

It would appear that the hypothesis is that some processes within the coral are driven by the amount of red light rather than blue. It is not clear from the summary article, but it appears that the author thinks this applies more generally to corals, not just one or some species. Interesting stuff.

I would love to get my hands on the full paper to see what red spectrum was used.

It is difficult to say what the implications are in aquariums without knowing what spectrum is involved and what the absolute levels of those specra are before harm results. All red is obviously very bad, but I doubt that anyone has near those levels of red in their LED lighting.

Roughly 2 years ago I remember reading a long article on Red light in corals and some experiments that were run. They used mainly Shallow water corals that received the full spectrum of the sun in nature. In nature these corals received PAR levels well over 2,000 for a considerable part of the day.

With studies on these corals they found that photosynthesis only occurred during the time periods the were between 30% and 60% of the normal maximum.

They then took some of these corals into the laboratory for some specific light frequency studies under controlled spectrum's. With a spectrum with a lot of blue light and no red light they found that coral growth was fairly proportionate to PAR levels between 100 and 600, but flattened out when they exceeded 600 and started to show coral deterioration when they exceeded 1,000 .

They ten added red light to in various percentages to the spectrum. It was found that when a certain level of red light was reached that photosynthesis slowed and even stopped completely regardless of the amount of light that the coral was receiving in the blue spectrum. It was also found that if enough RED light was given to the corals it would start bleaching them out.

As far as the wave lengths of red that they found I remember that the most sensitive wave length was just under 680nm. They emphasized this 680nm wave length as it was also the most powerful wave length for the growth of Cyano-bactera. However they also emphasized that all wave lengths above 630nm created similar sensitivity only to a lesser extent.

This older article popped into my mind as recently Dana Riddle wrote an article that shortly mentioned similar results from some of his experiments but he did go nearly into the same details on this as the long report I had read prior.

 

[Fredfish]

Interesting stuff Dennis. This most recent article is the first time I've seen anything on red light and photinhibition.

It still doesn't tell us anything about red light in aquarium lighting beyond the very general "too much is not good". To make this meaningful we would first have to know what the light levels of various red frequencies is in different types of aquarium lighting. Next we would have to construct some experiments to vary the red light on said lighting to find a point at which red light appears to affect the health of corals. Lastly we would have to repeat those experiments to validate them...

In nature these corals received PAR levels well over 2,000 for a considerable part of the day.

Has anyone ever put that much light of any type over an aquarium without bleaching? There are so many things affecting a corals health and this is ability to respond to stressors.

You know, looking at this last statement, it is entirely possible that, in our aquariums, corals are even more sensitive to red light.

 

[nicholasb]

The best reef tank lights are Halides. Many reefers are switching to L.E.D because of safety/heat, controllabillity, and not having to change the bulbs. If you look at all the succsesful reefers using L.E.D, who once used halides, most will tell you that the halides were only slightly better at growing corals, so so it's not worth switching back. You only have to look at the evidance to see that L.E.Ds work.