LED’s- No UV? Do corals need UV for longterm health?

[outhouse]

The n

LEDs labelled as "UV" are almost never actually UV. The ones in pre-built fixtures are all just violet in the low 400s, and you have to look hard to find true UV LEDs in electronics stores. Those are expensive and harder to work with than most of the common LEDs we run.

Also, I'm not convinced anything under the royal blue is worth adding. I don't think anything extra "pops" under violet LEDs when you turn up the rest of the lights. The amount you can add is very little because it's hard to gauge when you are going overboard.

The new V2 luminbars from reefbreeders, have a true UV 385 chips and the low 400,s making it a hair more like black light then say orpheks new UV light bars.

With the luminbar, you dont think there is a lot of light, until you take a picture with your phone, which shows how much light your really blasting down outside of our eyes ability to see.

 

[Reefahholic]

LEDs labelled as "UV" are almost never actually UV. The ones in pre-built fixtures are all just violet in the low 400s, and you have to look hard to find true UV LEDs in electronics stores. Those are expensive and harder to work with than most of the common LEDs we run.

Also, I'm not convinced anything under the royal blue is worth adding. I don't think anything extra "pops" under violet LEDs when you turn up the rest of the lights. The amount you can add is very little because it's hard to gauge when you are going overboard.

What about the Radion G5 UV channel? Does anybody know if it’s legit UV?

 

[JNalley]

What about the Radion G5 UV channel? Does anybody know if it’s legit UV?

It is not. They have no chips under 400nm.

 

[JNalley]

The lights that I know of that have true UV are:

GHL Mitras (385nm)
Orphek Atlantik & OR3 (390nm)
Kessil (390nm (I Think))
Gieseman Futura S (390nm)
Maxspect Jump series (390nm)

 

[J1a]

It seems that clams can in fact make use of UV radiation.

Iridocytes Mediate Photonic Cooperation Between Giant Clams (Tridacninae) and Their Photosynthetic Symbionts

Iridocytes, containing multiple stacks of proteinaceous platelets and crystalized guanine, alternating with thin cytoplasm sheets, are specialized cells that act as multilayer nano-reflectors. Convergence evolution led to their arising across a broad range of organisms, including giant clams of...

www.frontiersin.org

Perhaps by supplying some amount of true UV may cause the clam to change iridocyte amount/arrangements , and lead to change in mantle color?

 

[damsels are not mean]

The n

The new V2 luminbars from reefbreeders, have a true UV 385 chips and the low 400,s making it a hair more like black light then say orpheks new UV light bars.

With the luminbar, you dont think there is a lot of light, until you take a picture with your phone, which shows how much light your really blasting down outside of our eyes ability to see.

Interesting that there are some true UV leds in fixtures out there. To be honest, I'm betting it's just an attempt to justify selling you more "stuff". I am not convinced these fixtures will have enough UV to do anything even if UV did do something (seems the conclusion further upthread is little to no affect on coral growth or color). Too much of these LEDs and you could seriously damage lots of stuff in the tank. But too little, and you've spent a silly amount of money ans forced some engineering compromises for some LEDs that you won't even notice. Since sub 400 is invisible to humans for the most part it's impossible to eyeball it and you'd need some special tools.

 

[Big E]

The lights that I know of that have true UV are:

GHL Mitras (385nm)
Orphek Atlantik & OR3 (390nm)
Kessil (390nm (I Think))
Gieseman Futura S (390nm)
Maxspect Jump series (390nm)

I would look for some some independent tests on these to see if there is even enough UV penetrating the water to get to your corals. My guess is there isn't enough diodes in there to matter.

The only reason some of these fixtures even have them is for marketing.

The RB's high octance UV or Royal ice may have enough or something substantial to make it worth while, but I wouldn't buy either without and independent test over a tank and measured at different levels.

T5 bulbs have some so I'd be more inclined to go with that or even do some DIY with black light strips or bulbs.
You can find many spectral graphs showing the UV in T5 bulbs and they also have some IR in there for the complete package.

 

[JNalley]

Interesting that there are some true UV leds in fixtures out there. To be honest, I'm betting it's just an attempt to justify selling you more "stuff". I am not convinced these fixtures will have enough UV to do anything even if UV did do something (seems the conclusion further upthread is little to no affect on coral growth or color). Too much of these LEDs and you could seriously damage lots of stuff in the tank. But too little, and you've spent a silly amount of money ans forced some engineering compromises for some LEDs that you won't even notice. Since sub 400 is invisible to humans for the most part it's impossible to eyeball it and you'd need some special tools.

Maxspect Jump range is cheaper than anything anyone (big brands) else has to offer, even cheaper than AI Primes. So, the whole "Spend more money" thing is sort of out the window. As Dana has already said, UV can aid in the photosynthetic process even if unnecessary, and as has been recently pointed out, may allow for better/different coloration of clam mantles. I've stayed out of this talk because the simple fact of the matter is the science is unclear. While UV may not do anything perceptible within a Reef Tank environment (as far as growth and coloration goes) we simply don't know if it allows for other processes within corals, the science behind it is controversial, to say the least. What we do know, is that UV is present on the reefs themselves, so having it available in a light source is not without merit. Spectrum Measured below the surface of the water has been measured by BRS, and the lights that produce it show the UV (385-400nm) present below the surface of the water. If our end goal is to create a sun, having as much of the spectrum as a natural reef see's seems to be the best way to go about that...

 

[JNalley]

I would look for some some independent tests on these to see if there is even enough UV penetrating the water to get to your corals. My guess is there isn't enough diodes in there to matter.

Spectral tests of some of those lights have already been performed by BRS and you can clearly see the UV bump, it's especially noticeable when they do the surface agitation spectrum drift testing...

 

[Reefahholic]

It is not. They have no chips under 400nm.

Ouch! Can anybody confirm this is accurate? Why do they call it UV if it’s fake?

 

[Reefahholic]

The lights that I know of that have true UV are:

GHL Mitras (385nm)
Orphek Atlantik & OR3 (390nm)
Kessil (390nm (I Think))
Gieseman Futura S (390nm)
Maxspect Jump series (390nm)

Telegraham said GHL and Kessil’s. I think he measured those. Is he on R2R or only YouTube?

 

[JNalley]

Ouch! Can anybody confirm this is accurate. Why do they call it UV if it’s fake?

confirm it's accurate? That's taken directly off of their website...

 

[JNalley]

Telegraham said GHL and Kessil’s. I think he measured those. Is he on R2R or only YouTube?

Yes, those were the only two he knew of (he mentioned as much when he did the Mitras review) however, the others have been confirmed by me while researching lights. They have advertised nm LEDs from known LED manufacturers (OSRAM and CREE) who do make those nanometers, there's no reason to lie about it (and doing so would result in false advertising and lawsuits).

 

[Big E]

I would trust Telegrahm's test.........BRS I ignore for many reasons I won't get into.

If/when Dana gets a chance he would be a good source as well.

Whomever is doing the testing it's worthless unless it's done with a tank filled with water.

 

[JNalley]

Whomever is doing the testing it's worthless unless it's done with a tank filled with water.

How do you perform a surface agitation spectrum drift test without water?

 

[Reefahholic]

confirm it's accurate? That's taken directly off of their website...

I see that, but I’m taking about the 400nm. Does it absolutely have to be under 400nm to be considered UV? A quick google search says up to 400nm but again…I’m not a lighting expert. Not my strong area.

Sadly…I see the G5’s only make it down to 405nm.

 

[JNalley]

I see that, but I’m taking about the 400nm. Does it absolutely have to be under 400nm to be considered UV? A quick google search says up to 400nm.

correct up to, meaning 1-400nm = UV anything above = Near UV>violet>blue>etc

Edit: I should amend this to say that technically 380-~720 is the visible light spectrum as seen by the chart below. But, UV is considered anything below 400nm and InfraRed is considered anything above 700 I believe.

 

[Reefahholic]

correct up to, meaning 1-400nm = UV anything above = Near UV>violet>blue>etc

I just can’t understand why EcoTech would call it UV if it’s 405nm. Makes no sense to me. Wouldn’t some of these lighting guru’s call them out on that? How are we just now hearing about this? Did the G4’s have a UV channel too?

 

[JNalley]

I just can’t understand why EcoTech would call it UV if it’s 405nm. Makes no sense to me. Wouldn’t some of these lighting guru’s call them out on that? How are we just now hearing about this? Did the G4’s have a UV channel too?

I could be wrong, but I believe it stems from the fact that True UV has only been available recently, and the closest we could get was often 405nm+. The lighting Guru's HAVE been saying "It's not true UV" for a long while now, but no one has paid attention. It's close enough to UV to provide fluorescence, so people just ran with it.

 

[J1a]

I just can’t understand why EcoTech would call it UV if it’s 405nm. Makes no sense to me. Wouldn’t some of these lighting guru’s call them out on that? How are we just now hearing about this? Did the G4’s have a UV channel too?

Oh. This is probably because 405 nm is the peak wavelength, there is probably part of the spectrum falls in the UV (<400 nm) band. Take a look at a googled 405nm led spectrum.

FIG. 2. Spectral output of the 405-nm LED array used for bacterial...

Download scientific diagram | Spectral output of the 405-nm LED array used for bacterial exposure. from publication: Efficacy of Pulsed 405-nm Light-Emitting Diodes for Antimicrobial Photodynamic Inactivation: Effects of Intensity, Frequency, and Duty Cycle | Objective: This study investigates...

www.researchgate.net

I think there are two important questions to consider.

1. UV (UVA) covers 315 - 400 nm, but most diodes have very narrow spectral band. So which UV wavelength probably matters.

2. The optics needs to be UV transparent, and stablized. So this might not be a given.