Mitras Lightbar 2 Daylight LED Wavelengths

[photon]

Hello,

I'm new to GHL and your products. I am interested in the Mitras Lightbar 2 Daylight fixture. I would like to know more about the RGB LED emission wavelengths. I want to see how well they match the absorption spectra of plants. These are 430nm (deep blue), 453nm (blue), 642nm (red) and 662nm (deep red). And what about the green plant pigments from 500nm - 560nm? Can anyone help?

Thanks in advance.

photon

[PIWAWT]

11841

regards Pit

[photon]

Thanks for the information. I am confused by your choice of wavelengths for the blue and red LEDs. Please explain why you chose the wavelengths shown above. And, if you are using blue LEDs at 472nm, why is this not evident in the spectrum shown for the Mitras Lightbar 2 Daylight on your website? The blue peak occurs at approximately 455nm. Also, there is very little light in this spectrum at deep red wavelengths. The peak absorption wavelengths for chlorophyll a are 430nm and 662nm but the spectrum that you show has very low/low output at these wavelengths.

photon

[PIWAWT]

There is white 6500K and white 4400K in addition. White is always a mix of the basic colors (RGB) in LED's.
The pictures on the website are zoomed.
For example

118431184411845

regards pit

[PIWAWT]

sorry this is the right image with red and blue
11847

[pollymorin]

There is white 6500K and white 4400K in addition. White is always a mix of the basic colors (RGB) in LED's.
The pictures on the website are zoomed.
For example

118431184411845

regards pit

Thanks for the information. It really helped me!

[photon]

Hello,

It is me again.

I am returning to GHL because I want to be able to control the lighting spectrum for my planted tank. And GHL appear to have excellent controllers. But, as I said previously, I do not understand why you have chosen the following LED wavelengths for the Mitras Lightbar 2 Daylight:

Blue 472nm

Red 622nm

Please find attached the absorption spectra for chlorophyll a, chlorophyll b + accessory pigments. I would expect GHL to have chosen and used LEDs with wavelengths of 430nm and 662nm in order to best match the plant requirements. Choosing a red LED at 622nm could encourage the growth of BGA (cyanobacteria).

I look forward to your feedback.

photon

[Matthias]

The RGB part of the Mitras Lightbar delivers only a fraction of the light output of the total light. These LEDs run with about 15mA, while the High-Power LEDs deliver the significant part of the light respective the spectrum at > 500mA.
The RGB is intented for visual fine tuning and effects (sunset, moon, etc.) and has no negative effects.
As you can see white light includes also these wave lengths. So you have these wave lengths already in your spectrum. Increasing some peaks of the spectrum won't hurt.

You will have perfect results in growth of your plants with your Mitras Lightbar. If you fear growth of algaes or bacteria due to the RGB portion of the light then leave them switched off. We use them since years in our freshwater tanks with all RGB at 100% all over the day and had not once a problem of any kind.

[photon]

Hi Matthias,

Unfortunately, you have not answered the questions that I asked. I'm disappointed about that. I asked about specific wavelengths. Unless the Mitras LB2 incorporates LEDs emitting at 662nm, there will be insufficient light output at that critical wavelength to ensure optimum plant growth. It is not possible to rely on white LEDs to do this. Their output peaks in the blue region of the spectrum and reduces as the wavelength increases. May I draw your attention to the following:

"OSRAM Opto Semiconductors offers a broad horticulture LED portfolio for professional top lighting, inter lighting and vertical farming applications. Our High and Mid Power LED families include 660 nm (hyper red), 450 nm (deep blue) and 730 nm (far red). All important wavelengths in three different radiation angles 80°, 120° and 150° to support the perfect lighting for all types of plants and flowers".

Aquarium plants still share some of the same photosynthetic pigments as horticultural plants - particularly chlorophyll a and chlorophyll b.

photon

P.S. I have no affiliations with OSRAM. Other LED manufacturers, e.g. CREE could equally have made the same statement as that above.