mussel and hate
New member
It appears that some folks may have missed your point... So I will rehash.
White that is derived from mixing RGB has nothing to do with real white light. You ca get "white" from 3 spectral peaks that have zero ability to drive photosynthesis... It is not WHITE your brain just interprets it that way...
There is so much bad information in this thread that I would not even begin to know how to correct it.
Somebody said that a pile of LEDs are pretty much the same as a MH bulb... Just a bit different with regard to peaks...um no, not even close. A MH bulb emits light from a plasma arc, it by definition is continuous spectrum. It may have peaks, but there are no gaps in wavelengths. A pile of LEDs emits a very narrow pile of peaks with gaps in between.
Phoshpors? T5 and LED... Again worlds apart. The fluorscent bulb uses a mercury arc to create UV light. The UV drives the phosphor stokes shift. The same phosphors can not be used for LEDs because of the input wavelength difference. Decades of research went into FL phosphors. White light was a priority, as there is no way to create a reasonable RGB FL bulb to produce white light. In the LED world things are different. Read on....
I will say it again, almost everything we use in this hobby is a direct purchase from industrial stock. While white led phosphors are getting better, there is little drive for better white rendering when it is easier to build an RBG emitter that can be tuned to emit whatever pleasing color is wanted. The RGB emitter combo does solves the color rendering issue for humans, but is (again) devoid of much the spectral content required for photosynthesis. Not sure why so many folks are having trouble swallowing the reality... Until there is an industrial demand for LEDs with broad spectrum phosphors... There will be no LEDs with broad spectrum phosphors. Agricultural applications got their uv and deep reds, they don't really need whites, as they are looking for growth, not aesthetics and growth. Nobody in industry cares about my or your aquarium![]()
Am I to conclude from your statements that white LEDs do not stokes shift blue/violet to higher frequency light as fluorescent lamps do? Because last time I checked they seemed to do just that.
I don't believe anyone is claiming that a three peak RGB led array approximates sunlight. Your just setting up a strawman.
I'll agree that LEDs do not produce light anything like HID lamps do, that is totally different. But in my decades of reefkeeping using every light source available I've had the same successes and failures with specific corals regardless of light source. Water chemistry and feeding seem to be the determining factors for me. No lamp be it MH or anything else has the magical properties to overcome alkalinity swings, waste accumulation or nutritional deficits which in my experience and opinion are the most challenging hurdles.
There are some really nice tanks here such as Joe's but pictures of beautiful reef displays don't actually constitute proof of an argument. I know that's how it's done on the web these days but that is not reason...
MH, fluorescent and LED all work, what you prefer is another matter.