Causation of poor LED performance discussion

[gbru316]

Anyone who has spend time around here knows that LED vs everything is a hotly debated topic. Some have good results, some have poor results. I'm especially interested in discovering why some have switched to LED lighting, noticed decreased coral health (as indicated by coloration, polyp extension and tissue coverage), then switched back to their previous fixture and coral health improved, yet others have switched to identical fixtures and had great results.

Instead of arguing in circles, let's try to get to the root of the problem. Because after all, a photon is a photon, regardless of source.

I have my own theory, but I'm interested in what others have to say.

And, ladies and gentlemen, let's keep this civil. We don't need another thread running in circles discussing pros and cons

[PolyReef]

Quality of LED's,premium LED's(more$$)give you more photons to you tank?

[kory1006]

Tank maintenance plays an equal role if not more than the whole LED vs. all debate.

[sirreal63]

Not using an appropriate quantity of LED's for the tank's inhabitants.

[gbru316]

Originally Posted by kory1006

Tank maintenance plays an equal role if not more than the whole LED vs. all debate.

I agree, that's why I'm specifically interested in those with established tanks who have made the switch, noticed decreased coral health, then switched back resulting in an improvement.

[swanny]

"Cauasation of poor LED performance and let's get to the root of the problem". It sounds like you have already made up your mind that you don't like LED's. I'm not even quite sure what you are asking in this thread, lol.

[Donkeykong]

From all my research and reading I have seen several common factors for those that have failure with LED's.

1. Not enough units to meet requirements. With the high initial cost people tend to go to the low side of units recommended and then complain that they cant keep high light corals.

2.Not each Fixture is right for every tank. Deep tanks need LED's with optics to punch all the way down. I really like the EcoTech Radions but would never suggest it on a tank deeper than 24" as I feel it will not work well on deep tanks.

3. Corals take time to acclimate. If you are running halides and switch to T5's can you do it over night with no ill effects? NO and it seems that for whatever reason the switch to LED's is ever more drawn out. So many people end of burning there corals becuase they cant be patient when switching, and on the other side if they are patient the corals go through a flux of coloration as they adapt to the new light and then people complain that the corals don look the same.

4. It doesnt look the same. No LED's do not look the same as Halides, nor does Halides look the same as T5's. Some people just dont like the look and feel of LED's. This is your tank and you are the one staring at it for hours, if you dont like the way it looks change it. That is why I always tell people to actually go see the lights in person on multiple tanks to see if they truly like the look of the lights.

5. Not the problem. Lighting is not the only value in the equation. I have read experiences were people were having trouble with coral coloration and or growth. they switch back and had success, but also found a problem with alk or mag or stray voltage or something else along they way. But they were already soured to LED's despite other factors probably being the problem.

My conclusion is that LED's are great. They are not the silver bullet that solves all problems. They have limitations that make them poor choices for certain tanks, but that is true of all lighting. Do your research and figure out what would be required for your tanks specific needs. Then decide if LED's would fit your tank and if they would be cost effect for your tank.

P.S. this is all just my humble opinion.

[gbru316]

Here's my hypothesis, it's a combination of 2 ideas. Keep in mind, my field is electronics, not biology or physics, and that this is merely my interpretation of data and research i've collected and analyzed.

The first difficulty is application. It is difficult, if impossible, to create an LED array that is perfect over every tank. The directional nature of the emitters makes it so. Simple trig [tan(1/2 optic degree) * distance from aquarium bottom) will quickly show the radius of light produced will vary greatly with identical optics and different depths. This is why 2 people using the same fixture with 2 different tanks will always have different results.

The second comes in regards to spectrum. Dr. Sanjay Joshi is currently converting all of his tanks to LED. He states that as long as broad-spectrum light is provided, there is no reason that LED's do not work. For those that are unfamiliar with Dr. Joshi, he is an expert in marine lighting, and has done countless experiments and written many, many articles, based on science, on the subject. He started years ago with metal halide bulb testing, and created several charts advising which bulbs to use with which ballast to achieve good results. His testing uses high end testing equipment that is much too expensive for the average reefer to afford (He is a professor at Penn State, as a student at a Penn State branch campus, I can attest to the depth of the university's pockets, and the quality of equipment available).

If you look at his spectral distribution article, you can see that the LED fixtures provide a curve that is far smoother than the halide bulb tested against.

http://www.advancedaquarist.com/2012/3/aafeature

Specifically, every single LED fixture tested lacked in the near-UV (400-450 nm) and 500 nm range, as compared to the metal halide bulb. There are some other wavelengths that are not represented as well as MH too, but these are the most obvious.

The problem is that primary synthesis of violaxanthin, B carorene and lutein occur in the 417-452 nm range. Why is this important? Non-photochemical qenching.

Non-photochemical quenching is basically a process that allows photosynthetic organisms to regulate the conversion of light energy to sugars. Too much light energy, with no way to regulate it, results in photoinhibition.

When we combine the intense, directional light of LED's and strip the zooxanthellae's ability to regulate itself, we find decreased coral health.

Additionally, the lack of red in the LED fixtures results in a lower CRI, which impairs aesthetics. I believe that some red is needed to provide proper color rendering (it's also helpful because of chlorophyll a's secondary absorption peak at 655 nm), there is evidence that too much will impair photosynthesis and encourage algae growth.

[gbru316]

Originally Posted by swanny

"Cauasation of poor LED performance and let's get to the root of the problem". It sounds like you have already made up your mind that you don't like LED's. I'm not even quite sure what you are asking in this thread, lol.

au contraire, i fully support LED usage.

We have all seen posts stating that LED's don't work. I think it would be worthwhile to examine why they don't for some people, and why they do for others. I'm not asking for anything, other than discussion.

[smsreefer]

It seems to me one of the main keys with LED's is selecting the proper bin in regards to spectrum.
Proper binning and buying quality LED's seems to be talked about, but very often ignored in some of the builds going on.
[ I'm not saying everyone, but it IS happening ]

A par meter is also very useful when changing over to any light system, and I feel as though they should be used when ever possible, not only for the health of your corals but also for the baseline numbers you obtain for a true comparison of lighting.

One other factor that I believe plays a part is proper acclimation when switching out lighting systems.
Again, a par meter will tell you what you need to know and you can make adjustments as/if needed.

These are the first things that come to mind and for now I really have to head out the door.
I will check back later, this should be a great thread.
Have a great day,
David

[gbru316]

Originally Posted by smsreefer

It seems to me one of the main keys with LED's is selecting the proper bin in regards to spectrum.
Proper binning and buying quality LED's seems to be talked about, but very often ignored in some of the builds going on.
[ I'm not saying everyone, but it IS happening ]

A par meter is also very useful when changing over to any light system, and I feel as though they should be used when ever possible, not only for the health of your corals but also for the baseline numbers you obtain for a true comparison of lighting.

One other factor that I believe plays a part is proper acclimation when switching out lighting systems.
Again, a par meter will tell you what you need to know and you can make adjustments as/if needed.

These are the first things that come to mind and for now I really have to head out the door.
I will check back later, this should be a great thread.
Have a great day,
David

I agree, I also think there are mistakes made when trying to measure PAR. People fail to account for the response of the PAR meter when using Apogee meters, and the Li-cor meters are out of range for most of us.



As you can see, measured reading at 450 nm is about 50% of the actual value, and becomes worse as you head towards 400 nm.

The meter is only 100% accurate, requiring no calculation of error, until approximately 525 nm. Therefore, if one thinks they are reading 200 umol/m on the sandbed, they could be, and probably are in excess of 250 umol/m as most fixtures tend to utilize a large amount of 455 nm Royal Blue emitters.

[kbell2433]

I don't have LED's (yet), but in all the reading i have done on this and other forums, The people that went with LED have NOT switched back. Even the ones with the cheap LED's.

[rtparty]

Originally Posted by kbell2433

I don't have LED's (yet), but in all the reading i have done on this and other forums, The people that went with LED have NOT switched back. Even the ones with the cheap LED's.

Countless numbers of people have gone LED and switched back. A quick search will find you dozens of threads talking about it.

[kbell2433]

Originally Posted by rtparty

Countless numbers of people have gone LED and switched back. A quick search will find you dozens of threads talking about it.

The only thing i have read bad was about the 1 watt Led's, Not the 3 watt.

[rtparty]

I have shared my opinion in a number of threads but will quickly summarize it.

1) Spectrum - I personally find the the whole blue:white combo outdated and ugly. I have yet to see a bunch of good looking tanks using this combo. I am not talking pictures either, they are pointless. This is real life viewing. The blue:royal blue:white combo is old and should be done away with, unless that is white is Neutral White or Warm White. In that case there tends to be better color rendering going on. I still think it is a far cry from a good looking setup though.

2) Lack of patience - I think some people quit too soon and don't try enough to fix the problem. I understand that people don't want to wait and just want plug-and-play but you are in wrong hobby if 6 months is a "long" time. I am one of the people who almost gave up on LEDs and am glad I didn't! My problem was the LEDs themselves - it was me.

3) Like Jack said, not enough emitters - People think that LEDs are some magical light source and you can bend the laws of physics. This leads to issues for most of us, myself included. I read all of the horror stories of people frying their corals so I played it safe. I went in on the low end and paid for it. Once I added the PROPER amount of LEDs, things turned around very quickly for me.

4) Lack of knowledge - What do I mean by this? Well, let me put it this way. A trend I have seen is that people switch lights, tank looks like crap, they test their water and find out numbers are out of whack, they spend 1-2 months trying to fix it unsuccessfully and then blame everything on the LEDs. What people need to know is that when you switch lighting, you shock the system. Corals go into survival mode instead of thriving mode. It doesn't matter what lighting you switch to or from. Shocked corals will stop growing and therefore they stop sucking up the elements in our tank. Yet, we continue dosing like nothing has changed. This causes even more stress on the tank and starts a downward spiral. At that point people stop dosing and let nature work but they give up on LEDs and then give MH or T5 all the credit when their tank turns around.

All of this isn't new though. We fought the same type of issues back when T5 was introduced as ANOTHER type of light to use. It took a little while to figure out that the 50/50 combo of blue:white didn't work well with T5s either. Yet, we fell right into the same trap with LEDs.

Just my opinion though.

[rtparty]

Originally Posted by kbell2433

The only thing i have read bad was about the 1 watt Led's, Not the 3 watt.

There are PLENTY of threads about AI, Radions and other fixtures that all use 3w LEDs. You just have to look for them.

[BigBarnacles]

I agree with DonkeyKong's response (as well as parts of a few others). There is a well reputed LFS here in Chicago that runs LED's on almost every tank in there. Many of these tanks, if not all of them, were already well established. The growth and color in these displays have been amazing. After speaking with the owners I learned a few things. It takes the right type of LED's, size of LED's, and arrangement of LED's for good results. But just as importantly it takes great water quality (parameters). LED's aren't metal halides or T5's, they're their own thing. They are relatively new and rapidly improving every day. Personally, I'd never tell someone to choose one type of lighting over another, and the same applies to sumps, skimmers, etc. Either go with what works for ya or experiment with something new. Either way, we all need to share our experiences with others and accept others opinions for what they are. These are exciting times in the hobby, lots of new stuff to learn.

[kbell2433]

Originally Posted by gbru316

switched to LED lighting, noticed decreased coral health (as indicated by coloration, polyp extension and tissue coverage), then switched back to their previous fixture and coral health improved

Back to the original topic. I am waiting to see the people who have had this happen. I havn't seen anyone post yet, Im sure someone with this experience will post soon.

That is what the OP is talking about , sorry about getting off topic.

[stevedola]

Originally Posted by rtparty

2) Lack of patience - I think some people quit too soon and don't try enough to fix the problem. I understand that people don't want to wait and just want plug-and-play but you are in wrong hobby if 6 months is a "long" time. I am one of the people who almost gave up on LEDs and am glad I didn't! My problem was the LEDs themselves - it was me.

3) Like Jack said, not enough emitters - People think that LEDs are some magical light source and you can bend the laws of physics. This leads to issues for most of us, myself included. I read all of the horror stories of people frying their corals so I played it safe. I went in on the low end and paid for it. Once I added the PROPER amount of LEDs, things turned around very quickly for me.

4) Lack of knowledge - What do I mean by this? Well, let me put it this way. A trend I have seen is that people switch lights, tank looks like crap, they test their water and find out numbers are out of whack, they spend 1-2 months trying to fix it unsuccessfully and then blame everything on the LEDs. What people need to know is that when you switch lighting, you shock the system. Corals go into survival mode instead of thriving mode. It doesn't matter what lighting you switch to or from. Shocked corals will stop growing and therefore they stop sucking up the elements in our tank. Yet, we continue dosing like nothing has changed. This causes even more stress on the tank and starts a downward spiral. At that point people stop dosing and let nature work but they give up on LEDs and then give MH or T5 all the credit when their tank turns around.

I think asking people to wait 6 mths or more is asking a lot. It shouldnt take anymore than 2-4 wks to switch over lighting but there were so many with poor coral response to LEDs in the beginning that it made others scared and then went overboard on the transition and that led to bad side effects.

I do agree with you that there is a lot of misinformation/lack of knowledge on LEDS. People are told 1 thing and which is completely wrong and end up having a bad experience. I have been the guinea pig but have learned my lesson. Corals are expensive and to beta test lighting, additives, carbon dosing, or what ever else someone comes up with to make this easier has too much risk associated with it for me. Ive made my mistakes and until theproduct is hard tested, proven, with clear instructions I will not touch it. I cant afford to continue to dump money to chase corals Ive killed by testing products for manufacturers.

[bdare]

I have a 120 mixed reef tank with 86 Cree 3W LED's. I have a mix of CW and WW along with RB and 4 reds. I'm in LOVE with the color of my tank and really enjoy the fact I can change the color anytime I want if it looks too blue or too yellow to me from one day to the next. I've been running LED's for almost 2 years. My SPS have never looked better or grown any faster. Not sure why people have so many issues....

[PolyReef]

[PolyReef]

Very well said @stevedola personally i purchased several lamps from one of the manufactures from over seas and the quality of the led's was very questionable I'm using them form 07/2011 with no growth of the corals. LED lamps are still in the very early stages and even after all those years its a hit or miss when it comes to quality of the LED light in lamps. Many different technical issues are still not solved by the manufactures of the LED'S. A matter of fact no of those manufactures claim that the LEDS are reef ready. Mixing different colors of the less without a proper lens and reflectors is an nearly impossible task. Let me explain the different between fresh and salt water with penetration of light. Chemicals and salt will cause diffusion of light. The temperature of the light "kelvins" will fluctuate none efficiently because even we don't see it -every LED has a disco light effect. The lack of long term testing of lamps by greedy maufactures can cause on the end our losses not theirs. So Lades and Gentleman stick with a reputable LED lamp companies. Thank you and God Bless

[chilwil84]

from reading a lot of posts about switching from mh or t5s to leds it takes a long careful process to adjust your corals to the light. how do you add new coral to your tank that was lit from another source this could be a major source of issues for people with led tanks