Sunny Goold
Active Member
Gotta say Lasse your contributions here (I am going through the whole thread) are just fantastic - it would be amazing if this info was in a thread of it's own because it really is brilliant stuff - especially for a relative newbie like myselfBack to how we notice colours from other corals. Below a graph showing sensitivity of the human eye. If we see reflecting colours from 400 nm and 560 nm with the same physical strength – we will see the 560 as very much brighter than the 400 nm. In reality the wavelengths between 500 and 600 nm will dazzle your sight and if there are weak light sources, like fluorescence, you will not see its colours because the reflective wavelengths take over
If we only use wavelengths that promote florescence we will be able to see these weak light sources. One example is blue wavelengths like this below. Nothing will hinder you too see even the weakest colour source in the lumen window
Now we start to ad white LEDs We get a rather white looking aquaria but the wavelength between 500 and 600 will dazzle away all weak sources like fluorescence. We will see a lot of reflecting colours - but we miss the beautifully colours of fluorescence. They are there but we can´t see them - our eye does not detect them.
If we instead use single reed and green diodes and mix to 10 000 K - we gett some windows there it is possible to detect weak light sources for our eyes. This light is white - believe me and some of the fluorescence will show up. To use this RGB trick - it is easy to run an heavy blue tank but for your eyes - it is bright white
I normally run this set up for 8 hours a day
And this for around 3 hours
RGB LEDs is used by GHL Mitras LED bar 2 and is very good in order to obtain a whitish hue even when you run a very blue pattern. And it give the fishes beautiful colours too.
When I chose my set up - I chose one bar Oceanic blue 1 bar actinic and 2 bars deep actinic. The reasons for Oceanic blue is that it contain 10 pcs 4500 K LED (of 344 pcs of LED for my four bars) I want them because of that I want some LED that give wavelengths over 700 nm. I´m very sure that Far Red has importance even for corals (735 nm)
The chart below show the absorption peaks for some single isolated chlorophylls - It not the same as the whole organisms absorption.
If you made a comparison between my charts here and charts for MH - you will note that there is no wavelengths below the radar as we no it for the moment. If other facts will show up later on - with a LED fixture - its easy just to add these monochrome LED that´s will be needed. I have one bar - done by my self - with only 735 nm far red- will add this later on.
I prefer - for my self to work with green and red monochrome diodes instead of getting these wavelengths from "white" LEDs. As far as the - IMO - rather ridicules fear for red monochrome LEDs - just look att spectra for MH and/or low Kelvin white LEDs - there is tons of red wavelengths in these sources. But if you run 4500 K in heavy way - you maybe not should add tons of 660 nm LEDs.
One last thing - the use of PWM dimming. The photosyntetic process is by natur a quantum mechanical process - it means that it act in a digital maner - on/off with a frequency. The wet dream would be to find this frequency and send out photons of the right wavelengths and with the right frequency in order to optimize this. The problem, however - what is the frequency and how stable is it? What´s happen if the frequency is wrong? Some commercial producers of LED fixtures for green houses do only use PWM for the first 10 % and after that 1-10 V signal to manage the current. Are there any biological reasons for that? I do not know and probably will not ever know - but since I realized this - I run at 100 % or limit the current. Just ramp up and let it be there.
Sorry for long post
Sincerely Lasse
