thinking of switching back to LEDs???

[dkeller_nc]

A someone with a science education, there's an aspect to these kind of posts that I find very odd. Namely, that a "type" of light is better/worse/killed my corals, etc...

Photons don't care what originated them - they all travel at the speed of light, and have a characteristic energy level (frequency). That's it.

So the only thing that's relevant to the type of light argument is what mixture of photons it puts out (spectrum), how many it puts out per unit of time (intensity), and, possibly, if the light emitted is a point source and whether the light coming from it is polarized.

It doesn't surprise me that folks have found that reproducing just a small portion of the spectrum isn't good for corals, nor that switching a light source without being careful can burn/bleach corals. But attributing those problems to the device that puts out the light seems a bit weird - you can certainly burn the crap out of corals with a MH placed too close or with too much wattage.

 

[jda]

As a scientist, can you explain to all of how us how photons have feelings enough to care about anything? I am just kidding. I do think that it is a bad assumption to think that different methods of artificially reproducing something to mimic something natural will all lead to the same results and specifically that each method will have the same amount of other trash given off as well.

You can put SPS a few inches under the water under tons of MH or even outside in the sun with PAR readings over 800 or 1000 and they just thrive. There is something else going on with LEDs that nobody knows about yet and just assuming that photons are all that is being produced is probably not a good idea.

 

[jerpa]

As a scientist, can you explain to all of how us how photons have feelings enough to care about anything? I am just kidding. I do think that it is a bad assumption to think that different methods of artificially reproducing something to mimic something natural will all lead to the same results and specifically that each method will have the same amount of other trash given off as well.

You can put SPS a few inches under the water under tons of MH or even outside in the sun with PAR readings over 800 or 1000 and they just thrive. There is something else going on with LEDs that nobody knows about yet and just assuming that photons are all that is being produced is probably not a good idea.

And this is where you lose me....

Missing spectrum? Possibly. Overwhelming intensity over narrow ranges of wavelengths? Maybe. An array of narrow point sources causing the coral to receive different light spectrums on different areas of the colony? That's believable IMO. Single point sources that create such unnaturally harsh shadowing that may impact the health of the entire colony? That's plausible. The idea that LED photons themselves behave differently. Simply not true. I definitely don't believe that they are generating some sort of immeasurable energy that produces lackluster color in certain corals and complete death in other tanks.

 

[jda]

I never said that the photons in the correct spectrums behave differently. To put it another way... in an effort to artificially reproduce the same photons, the diodes could be putting off other things that are harmful in addition to the good photons.

This is totally possible. HQI puts out immense amounts of harmful radiation that, unless shielded, will kill most of what is in your tank over time. It took a while to get this right...and it went for a while without being measured, quantified or "known." There are numerous types of devices that put out photons that also put out other stuff that is harmful to living things - those food warming lights, tanning beds, etc. It it totally that possible that LEDs are doing the same thing, and likely IMO, since other lighting source with PAR readings of more than twice the amounts of LED don't harm coral at all, and most flourish under it.

Fluorescent tubes needed a lot of development to get right.

It could be UV. You can search all over the web and see that a blue diode or two puts out a insignificant amount of UV radiation to humans (although this is not qualified or quantified)... and that white diodes, in their studies, are actually blue diodes with a different film over them, so they assume that the behave the same way. I can find no study or test where someone puts hundreds of these things over a small area to creatures/things that rely on light for survival more than humans. It might not be UV. I don't know - I am just saying that it is possible. Is it possible that the long time needed to adjust is the coral building up some sort of filter or slime to protect it's self from UV. Again, I don't know, but it is possible. It has happened with nearly every light source brought to market so far, so why not this one?

Here is what I think is happening. The diodes put out too much UV radiation, but not like unshielded MH does, so the most coral lives and just time to adjust, if it will at all, and the adjusted corals will eventually be pretty good, and the ones that don't adjust just suffer. I am not a pro... I didn't even sleep at a Holiday Inn Express last night... but something is different and it goes way beyond photons.

 

[CHSUB]

No, chsub blames his tank crash on LEDs. This is his way to just blast LED users. I wish they would make him move on! This is another example of someone putting information out there with a hidden agenda.

"hidden agenda"???? that is funny....just having fun, this is a hobby right?


no tank crash, just wild and maricultured acro's failed under LEDs. all other corals did fine including birdsnests and other "easy" sps' along with leathers and such....however, i do find issue with some posts on RC regarding LEDs. take the post below, for example. he first tells us how smart he is being "someone with a science education". i guess that makes him more creditable. he goes on to say that he finds it "odd" or "weird" that someone would even consider a light source as a potential problem as "Photons don't care what originated them". i assume that's a polite way of saying he can't possible fathom how stupid or ignorant i am for thinking anything different.
i have seen some stunning led lit tanks filled with sps', however any experienced reefer will readily admit MH do a better job. i think the debate stems from "newbie" reefers who use leds and after a couple of months proclaim how leds grow and color sps' better than MH. years ago there was only one lighting source that was capable of growing sps' and it was MH and all the barriers to using them included chillers, more plumbing, larger pumps etc. i had a reef for 5 years before i had a set-up worthy of sps'. Today someone sets up a tank, throws a led over top, read a couple of articles by randy, and 5 months later he’s a RC expert aquarist giving advice on how to keep sps’ under LEDs. i wish "they would make" (as you said) people have more experience before giving advice.

A someone with a science education, there's an aspect to these kind of posts that I find very odd. Namely, that a "type" of light is better/worse/killed my corals, etc...

Photons don't care what originated them - they all travel at the speed of light, and have a characteristic energy level (frequency). That's it.

So the only thing that's relevant to the type of light argument is what mixture of photons it puts out (spectrum), how many it puts out per unit of time (intensity), and, possibly, if the light emitted is a point source and whether the light coming from it is polarized.

It doesn't surprise me that folks have found that reproducing just a small portion of the spectrum isn't good for corals, nor that switching a light source without being careful can burn/bleach corals. But attributing those problems to the device that puts out the light seems a bit weird - you can certainly burn the crap out of corals with a MH placed too close or with too much wattage.

 

[mikeatjac]

"hidden agenda"???? that is funny....just having fun, this is a hobby right?


no tank crash, just wild and maricultured acro's failed under LEDs. all other corals did fine including birdsnests and other "easy" sps' along with leathers and such....however, i do find issue with some posts on RC regarding LEDs. take the post below, for example. he first tells us how smart he is being "someone with a science education". i guess that makes him more creditable. he goes on to say that he finds it "odd" or "weird" that someone would even consider a light source as a potential problem as "Photons don't care what originated them". i assume that's a polite way of saying he can't possible fathom how stupid or ignorant i am for thinking anything different.
i have seen some stunning led lit tanks filled with sps', however any experienced reefer will readily admit MH do a better job. i think the debate stems from "newbie" reefers who use leds and after a couple of months proclaim how leds grow and color sps' better than MH. years ago there was only one lighting source that was capable of growing sps' and it was MH and all the barriers to using them included chillers, more plumbing, larger pumps etc. i had a reef for 5 years before i had a set-up worthy of sps'. Today someone sets up a tank, throws a led over top, read a couple of articles by randy, and 5 months later he's a RC expert aquarist giving advice on how to keep sps' under LEDs. i wish "they would make" (as you said) people have more experience before giving advice.

This is a hobby but this site is where reefers often do of their research. And YOU are doing a big disservice to anyone that reads your comments. I have read your build thread and your losses could have been from many factors. IMO Reef Central would be a better place without your misleading involvement.

 

[CHSUB]

This is a hobby but this site is where reefers often do of their research. And YOU are doing a big disservice to anyone that reads your comments. I have read your build thread and your losses could have been from many factors. IMO Reef Central would be a better place without your misleading involvement.

how about someone that insists that there are not issues with LEDs and some corals; or manufactures and distributors that display tanks with colorful, large sps' and claim they were grown from frags when the lamp has been out for only a year or so. many have had the same experience with LEDs that i have had. your the one doing a disservice by claiming your 3 months of using the "PRO's" makes you an authority on LEDs.

 

[mikeatjac]

how about someone that insists that there are not issues with LEDs and some corals; or manufactures and distributors that display tanks with colorful, large sps' and claim they were grown from frags when the lamp has been out for only a year or so. many have had the same experience with LEDs that i have had. your the one doing a disservice by claiming your 3 months of using the "PRO's" makes you an authority on LEDs.

I also said that I had g1s for six months prior to upgrading to pros in answer to your question you asked me. I never said i was an expert on anything but that i was having a good experience with LEDs. Really I feel that RC should have moved you on. To intentionally mislead people is very wrong!

 

[dkeller_nc]

It could be UV. You can search all over the web and see that a blue diode or two puts out a insignificant amount of UV radiation to humans (although this is not qualified or quantified)... and that white diodes, in their studies, are actually blue diodes with a different film over them, so they assume that the behave the same way.

It turns out that LED fixtures available to the hobby at the moment are just starting to produce some very low-energy UV (frequencies greater than 380 nm). In fact, the spectrum of most of the LEDs on the market lack UV of any significant amount compared to high output fluorescent and metal halide fixtures.

I've no proof for this assertion, but I do suspect that some of the issues with LEDs and coral growth is precisely the lack of UV.

 

[dkeller_nc]

take the post below, for example. he first tells us how smart he is being "someone with a science education". i guess that makes him more creditable. he goes on to say that he finds it "odd" or "weird" that someone would even consider a light source as a potential problem as "Photons don't care what originated them". i assume that's a polite way of saying he can't possible fathom how stupid or ignorant i am for thinking anything different.

No, "science education" doesn't equal "smart", it equals trained. In this case, I find the attribution of poor growth/failure of SPS to the device generating the light rather than the spectrum/intensity of the light odd. But that's the attribution/description that I find odd, not the person making the attribution.

 

[dkeller_nc]

Those interested in the scientific study aspect of light sources might like this article:

http://www.advancedaquarist.com/2013/2/aafeature

I find a couple of aspects of this study interesting. LEP has a very similar spectrum profile to metal halides (in fact, a LEP pretty much is a metal halide using RF as a driver), and the LEDs in this study were the older style - white, blue and royal blue (no red, green or UV).

Nevertheless, neither light source was completely successful with all corals. It seemed to greatly depend on the species, which would make sense considering that the ones selected for the study were adapted to different depths on the reef.

 

[ksicard]

I'm no expert by any means but I learned how to build led fixtures 2 years ago after stumbling on to nano reef forums and seeing all the projects that people had produced for their tanks. So before I began building them I heavily researched led fixtures in all the aspects I could think of such as, coral reaction/growth, heat output, temperature, led diodes and how they work along with how and the type of light they produce, along with many other factors and all the different companies and what not. So here's my opinion on the matter, which is strictly my opinion based on what i've learned and the fixtures I've built and how my corals reacted.

All artifical light produced by the different types of lighting, MH, t5, led's....... all produce the same type of light, corals do not care what type of fixture produces their light source because they all produce the same type of light and they are unable to tell the difference between the different light sources. But what is different about the light produced from the fixtures is the intensity, color temperature, and how the light is cast out (led's produce light in narrow beams, while MH/t5 emit their light in a much broader fashion). We all know how intensity of the light works and that corals need to be acclimated to higher intensities and what not. Led's tend to be the most intense out of the 3 depending on the setup due to not only being adjustable but mainly due to the different optics that are available, with MH's being second, and t5's falling behind the other 2 (of course there are exceptions to this depending on the fixtures and what not, but this is just my general understanding).

And the 2nd difference is the color temperature produced by the different fixtures, which is what I spend the most time researching. MH and t5 have all the different bulbs that are all rated at different kelving ratings, the typical trend seems to be lower K results in faster growth with a more white look while the higher K results in the more blue look but tends to bring colors much more and some also say corals color up better in general with a higher K lighting. I spent a lot of time researching this for my LED builds since Led diodes are limited to producing a specific Kelvin compared to mh and t5 where their bulbs tend to have a much broader spectrum of light being produced (I also forgot to mention that MH and t5 release small bits of UV, particulary the hqi setups). The most common problem I see with LED fixtures made by companies is that the spectrum created by their led combinations tend to be limited and are made to appeal more to how the tank looks to the eye rather than what's more valuable to the corals. So that's the main reason why I build my own led fixtures, this way I can setup my led's to produce a spectrum of light that I think is more benefical to corals growth and coloration. Most led fixtures are missing the trace amounts of uv along with purple/UV led's and also the ratio of the different colored led's tends to be off. With most LED users using commercially sold fixtures I think a large problem occurs with setting the fixtures up correctly in terms of intensity and color spectrum where as mh/t5 is much more hands off where you just plug it in and choose the bulb with your preference on Kelvin rating. So basically a lot of led failures I think are due to user error along with the preset led diodes and ratios that they are in.

The 3rd difference is how the light produced is emitted. MH/t5 produces light in a much more broader way that I think is superior to led's narrow light source for 1 main reason. This is something that i noticed first hand in my tanks, with my led's I noticed that if my sps are planted completely vertical that shading occurs on certain parts of the branches that are underneath the top of the frag or colony, so I started compensating by angling all my corals in a way that the light could hit more of the coral, but this leaves the back side of the coral shaded. MH/t5 don't require this angling method and tend to cast light in a way that it hit's much more of the coral regardless of whether it is directly in the light. So with larger colonies I think their overall health could be much better since mh/t5 tends to bend better than led's so the mh/t5 setups would provide light to the base of the colonies and the parts that are underneath the branches. I don't know if that's the scientific answer to it or not but it's something I noticed inside my own tanks, Led's are not as efficent as mh/t5 when it comes to lighting areas that are not directly in the led's light beam which can lead to stn of larger sps colonies and deterioating health of the sps colony on the bottom half of it.

So my basic overview of it all is that the 3 main types of lighting all produce the same type of light which corals can not tell the difference between what type of fixtures produces their light source but the differences lie in the intensity of the light produced, the color spectrum of the light produced, and how the light is emitted from the different types of lighting. All 3 play a major role in how the coral grows, colors, and overall health of the piece. There's also loads of other differences between the 3 but those are the main differences I've noticed in terms of the actual light that is produced into the tank which is what the corals are all soaking up aka the most important thing when it comes to our sps tanks. All 3 types of lighting can grow and produce beautifully colored sps corals efficently, I don't think anyone can say what lighting produces the best colored sps corals and which can grow them the fastest since there are many factors that take place that affects this. Also when switching between the different types of lighting the corals will need a break in time before anyone can say that this type of light can't grow or color sps as well, typically it takes between 3-9 months for SPS to completely adjust to the new lighting, the time it takes to adjust varies since sps is so diverse. Some corals start growing/encrusting right away while others take half a year before they do anything, but after enough time in my tank they always seem to adjust and take off in growth if given the proper environment to thrive.

I will not say nor do I think anyone can say that any light source is inferior to others, they all have their pro's and con's and I think it really just depends on what your comfortable with. Personally I don't think I'll ever change from led's, mainly because I have a lot of fun building them and the control that they offer beat's out the other types of light in a huge way. Being able to create sunrise/sunsets and being able to adjust the differenent diodes to exactly what I want is just awesome, I typically change my kelvin temperature every two monthes switching between a lower kelving and a higher kelvin to offer my corals the best of both worlds (faster growth/better coloration).

Sorry for the lengthy post, but that's a general idea of what i've researched and noticed inside my tanks. I'm not saying that I'm right and every body else is wrong or anything like that, but the above is just my un biased opinion on the different types of lighting and the affects it has on my tanks (and yes I've owned all 3, and never once did I blame my lighting on why my coral wasn't looking great or dieing, all 3 can grow and color coral well).

 

[CHSUB]

No, "science education" doesn't equal "smart", it equals trained. In this case, I find the attribution of poor growth/failure of SPS to the device generating the light rather than the spectrum/intensity of the light odd. But that's the attribution/description that I find odd, not the person making the attribution.

Kudos to you for such a dignified and on point response, and I tend to agree with your intensity/spectrum hypnosis. It is quite evident that LEDs can grow some amazing corals. However, the reefer of the best LED lit tank I have seen confesses that he has trouble with maricultured acros; and he still believes MH color and grow sps' better than LEDs. His words not mine. There appears to be limitation with LEDs and some sps'. These are my experiences and many others. I believe it is our duty as reefers to highlight these shortcomings of LED lit reefs. I was duped by a manufacture/distributor into buying a product that they neither knew or cared could grow sps'. They did and continue to display beautiful sps' reefs under LEDs and claim the corals were grown from frags. when it's quite clear that many of the corals are maricultured and newly added, as the bases are a dead giveaway. I think we should send a message to the manufactures that we are not going to be their "œguinea pigs". They should do the research and produce a better lamp and stop blaming the reefer for failures. There a many studies that red spectrum light bleaches corals yet lamp makers continue to increase the amount of red in their lamps? Take note of the post below, as I have many of the same concerns regarding LEDs and sps'.

it should also be noted that I'm not trying to intentionally deceive anyone. My post was obviously an attempt at humor and many found it that way. I have more to gain from "œhyping" leds as I have been a buyer/seller of Cree stock for many years. it is still a bargain at a p/e of 114 !!!!

Missing spectrum? Possibly. Overwhelming intensity over narrow ranges of wavelengths? Maybe. An array of narrow point sources causing the coral to receive different light spectrums on different areas of the colony? That's believable IMO. Single point sources that create such unnaturally harsh shadowing that may impact the health of the entire colony? That's plausible.

 

[dkeller_nc]

There a many studies that red spectrum light bleaches corals yet lamp makers continue to increase the amount of red in their lamps?

If you take a look at the study I linked to, they're a couple of major differences between the LEDs used and the LEP lamps as far as spectrum is concerned. Specifically, the LEDs are first or 2nd gen lights with blue, royal blue and white only.

There's a spectrum comparison graph in the article, and it's fairly obvious that the LEP (essentially, a high-tech metal halide) has a very broad, full spectrum that includes substantial UV and yellow/red. The LED (the Vertex Illumina, I think) fixture was very blue, with virtually no UV and little in the way of yellow/red.

My interpretation is that to be more effective as a coral reef tank light, the manufacturers do indeed need to add red, yellow and UV to their LED setups. It may even turn out that some degree if infrared is important to some shallow-water corals.

Here is a video by Mike Paletta and Sanjay Joshi

http://www.youtube.com/watch?v=N4yIEIM1R48

Essentially, their experiment was about LED lights, but Mike was using the AI Sols, which are only blue and white LEDs (though he did add some auxillary red and greens, but low power) Their observations are interesting.

 

[AquaTDV]

I run a 60 cube with a DIY LEP/LED fixture... I find it extremely challenging to grow many sps and lps under this light, even though its tied to a 240 that is a healthy 9 year old mixed reef. At 100% I've found that its par numbers aren't that impressive but there is something about the intensity of this light that many corals reject under a normal 8 hr photo cycle. I've only had success with certain Torts, green Milles, and purple Digi take on a whole new look like nothing I've ever seen before. So I switched directions and went with a "high" light tank. This light would be ideal for someone running a light rail or used for 4 hours or less a day, just to supplement your primary lighting. Par seems to have little to do with intensity from a corals perspective.