Red Light - Good or Bad for Corals?

[Robthorn]

No sir I do not. A couple water changes with a different brand and a wholesale change of dosing elements has started to show some slow improvement.

Sorry for sending the thread sideways.

Rob, do you have a thread open on your issue? I'm curious about the details and might have some ideas, but I don't wanna side-track this thread.

 

[Dana Riddle]

Thanks to all of you, I am learning a lot here!

I would very much like to know of some research that evaluated the ability to protect or cure some frequency of the blue spectrum in relation to corals. It is known that Pseudomonas sp. is a frequent presence in domestic aquariums and may cause imbalances in both fish and corals, but it would be interesting to find out if any "engineering" in the design and spectrum of our luminaires could somehow contribute to the control of the microbial imbalance that can occur in our tanks. On the other hand, it would also be interesting to know how much the spectrum of luminaires can interfere, for example, in the results of bacterial probiotic dosages and whether it would matter or whether, in the light of this knowledge, the administration of bacterial blends with light or off.

Best Regards

Bruce Carlson brought up a related topic back in the late 90's on a now defunct website - Could UV generated by a metal halide lamp act as a sterilizer? I have a programmable water bath incubator and could run some tests if I can obtain the correct broths...

 

[Jose Mayo]

Bruce Carlson brought up a related topic back in the late 90's on a now defunct website - Could UV generated by a metal halide lamp act as a sterilizer? I have a programmable water bath incubator and could run some tests if I can obtain the correct broths...

Yes, the bactericidal effect of the UV spectrum has always been widely discussed, but it evidently also poses risks to the health of the exposed animals. With the blue spectrum, some frequencies appear to exhibit a bactericidal effect, but without affecting, as far as is known, animal cells. If this is true, can it be that, in an optimal photic zone for some coral species, light plays an important role in controlling bacterial load, in addition to other defenses? That is my question.

 

[Jose Mayo]

In another vein, thinking of the blue spectrum and thinking only of the spectral differences between filamentous, fluorescent, and LED lamps, it may be said that filamentous and fluorescent lamps exhibit a "broad blue spectrum," whereas LEDs exhibit a "specific spectrum," which can bring about differences in the influence of light on the environment of the aquarium and on the behavior of corals, be it due to lack or excess of some of the frequencies of the spectrum.

Best regards

 

[jantje]

No idea what the official story is.
But yea, a few members got them from Europe , and few Europeans are running them.

a few.....already in my area 40 km around my house i know 8 tanks with Coral Care

 

[jantje]

What was the reason in the end?
Are they still a live product in the EU?

for sure....a lot of users switched due to the coralcare from T5 to CC led. And several LFS also switched.
In the Holland and Germany they are very popular, myself...i am very happy with them above my red sea 650 Max.
Good growth of the Coral, less powercomsuption, no noise !, no changing tubes anymore and most imporaant for me...no adjusting, tunning or find out how to make a good colorscheme.

 

[mcarroll]

If this is true, can it be that, in an optimal photic zone for some coral species, light plays an important role in controlling bacterial load, in addition to other defenses?

I don't recall if any lighting concerns are specifically discussed, but Microbial Community Management in Aquaculture does get into many other related issues in the same vein. Could be interesting for anyone willing to experiment!

 

[Jose Mayo]

I don't recall if any lighting concerns are specifically discussed, but Microbial Community Management in Aquaculture does get into many other related issues in the same vein. Could be interesting for anyone willing to experiment!

My point is that many luminaires have been and are being launched, LED-based, replacing the "old" HQI and T5, but ... the promised results are not always achieved. Perhaps there is a lack of concern, in addition to PAR and PUR, with the other aspects related to lighting, such as these effects on the environment, which are beyond what is being researched today for aquarism.

I would like to know that the lamp I am buying does more for my animal than just "feed it", however I may be just a visionary, and there is no practical advantage or utility in it.

Best Regards

 

[oreo54]

In another vein, thinking of the blue spectrum and thinking only of the spectral differences between filamentous, fluorescent, and LED lamps, it may be said that filamentous and fluorescent lamps exhibit a "broad blue spectrum," whereas LEDs exhibit a "specific spectrum," which can bring about differences in the influence of light on the environment of the aquarium and on the behavior of corals, be it due to lack or excess of some of the frequencies of the spectrum.

Best regards

Well known issue in the "real world".. you know where 90% of LED lamps will be sold.

Some are pushing for violet based emitters and using RGB phosphors to emulate natural light.. oddly enough just like t5's ect..
Filaments are practically dead, for the most part..
http://trir-pj.com/en/cob-specification-update-2016/
BUT who will build a phosphor targeted violet chip specifically for reefs.
That said there is plenty of overlap in "blues" to be just as broad as most other lighting..
http://spectra.1023world.net/

UV (390nm)- cyan (500nm).. every 10nm...

.. speculation.

now back to the "problem"..you just have to convince them to do blue centric phosphor pack..
Point is "better" LED's are possible now.. just not "practical"...

 

[Lasse]

About UVC - there is only one narrow wavelength that is germicide - 253.7 nm. In water with particles smaller than 5 my it will only reach a depth of app. 5 cm. Forget germicide actions of MH but some other wavelengths below 400 can alter cells through active radicals but can´t destroy DNA itself as I have learned

Sincerely Lasse

 

[Jose Mayo]

About UVC - there is only one narrow wavelength that is germicide - 253.7 nm. In water with particles smaller than 5 my it will only reach a depth of app. 5 cm. Forget germicide actions of MH but some other wavelengths below 400 can alter cells through active radicals but can´t destroy DNA itself as I have learned

Sincerely Lasse

Yes, that was the understanding, but today it is known that some frequencies of the blue spectrum, from 405 to 470 nm, have bactericidal effect at least for some groups of bacteria, although not for DNA damage.

Best regards

 

[Jose Mayo]

I found this now, which reinforces what we talked about above:

Photoinactivation of major bacterial pathogens in aquaculture

Highlight: "We successfully demonstrate inactivation activity of a 405/465-nm LED on selected bacterial pathogens. Although some bacteria were not fully inactivated by the 465-nm light, the 405-nm light had a bactericidal effect against all seven pathogens, indicating that blue light can be effective without the addition of a photosensitizer. Photobacterium damselae, Vibrio anguillarum, and Edwardsiella tarda were the most susceptible to the 405-nm light (36.1, 41.2, and 68.4 J cm−2, respectively, produced one log reduction in the bacterial populations), whereas Streptococcus parauberis was the least susceptible (153.8 J cm−2 per one log reduction). In general, optical density (OD) values indicated that higher bacterial densities were associated with lower inactivating efficacy, with the exception of P. damselae and Vibrio harveyi. In conclusion, growth of the bacterial fish and shellfish pathogens evaluated in this study was inactivated by exposure to either the 405- or 465-nm light. In addition, inactivation was dependent on exposure time."

Best regards

 

[Lasse]

This is a lab experiment and with a high energy flux - much more than we get from a MH in these wavelengths. A fast calculation says that in PAR numbers it corresponds of a level around 250 for the 405 nm and 516 for the 465 nm source. A PAR level of 250 only for the 405 wavelength should correspond to an enormous PAR figure for a multi wavelength source as MH. Correct me if I´m wrong – its early in the morning here.

However, this raise another question – can the heavy use of blue light in our aquariums damage our eyes because the mechanisms seems to be similar – production of oxygen radicals

Sincerely Lasse

 

[Jose Mayo]

However, this raise another question – can the heavy use of blue light in our aquariums damage our eyes because the mechanisms seems to be similar – production of oxygen radicals

Well, at least in fish, there are studies that indicate there is no damage to the retina by exposure to light from the blue LED:

The effect of spectral composition and light intensity on melatonin, stress and retinal damage in post-smolt Atlantic salmon, Salmo salar

Best regards

 

[Jose Mayo]

Well, at least in fish, there are studies that indicate there is no damage to the retina by exposure to light from the blue LED:

The effect of spectral composition and light intensity on melatonin, stress and retinal damage in post-smolt Atlantic salmon, Salmo salar

Best regards

But ... yes, there is evidence that exposure to blue light, at least at lower frequencies, can cause cumulative damage to the retina in rats and perhaps in humans:

Effects of blue light on the circadian system and eye physiology

Best regards

 

[mcarroll]

However, this raise another question – can the heavy use of blue light in our aquariums damage our eyes because the mechanisms seems to be similar – production of oxygen radicals

Yes. I've know several folks in the biz whose eyedoctors called them on it during an exam. They could tell.

 

[mcarroll]

Well, at least in fish, there are studies that indicate there is no damage to the retina by exposure to light

400,000,000 years with no eyelids will do that, eh?

 

[Jose Mayo]

400,000,000 years with no eyelids will do that, eh?

This is very likely the answer, for fish ... already in our eyes, besides the eyelids, we have the ability to collimate the lights of our aquariums so that at least the incidence on our eyes is not direct, the which should greatly soften the problem.

Best Regards

 

[Lasse]

I have not access to the whole article - exposing time has a huge importance’s for human beings. In Sweden (and probably Scotland also) there is concerns of blue light at workplaces just because of the risk for damage of the retina – that’s probably the reason why this investigation on fish take place.

At the moment – there looks like normal use of LED devices – screen devices and other digital equipment’s is nor harmful – but the heavy blue light of a saltwater aquarium – I have always wonder about

Bur this is a side discussion for another thread – This thread its about red - red wavelengths is not harmful for humans – but are they harmful for corals?

One reflection to earlier post. Maybe a misunderstanding – I have not seen any morphological changes between aquarium with red wavelengths between 600 – 700 nm compared with others without these. But I have seen differences between aquaria that does not have any wavelengths over 700 nm and aquaria with a lot of wavelengths over 700 nm. The one I have compared have all been rich in wavelengths 600 – 700 nm. Corals that have been moved between this aquaria – quickly change their phenotype. I´m not sure that the morphological differences is due to wavelengths over 700 or not but I´m just now testing this idea but it will probably take a couple of months before I know if this a brain ghost or not



Sincerely Lasse

 

[Jose Mayo]

Bur this is a side discussion for another thread – This thread its about red - red wavelengths is not harmful for humans – but are they harmful for corals?

You're right to say that I've escaped the purpose of the topic, I apologize for it.

Best regards