[GpsFrontier]

The majority of plants do not react along certain wavelengths, and this can be verified with a simple CO2/O2 exchangemeasurements or via protein fluorescence observations.

In fact, a majority of non-woody plants will have adverse reactions to exposure to green light, such as stunted growth or hindered reproduction. Trees, on the other hand, need green light to fulfill their full reproductive cycle properly.

I would like to see the research that supports the statement that plants don't respond to wavelengths of green light. Green light is 1/3 of the full spectrum of light (wavelengths), and that would be saying plants have adverse effects to natural sunlight. That's what I would call unfounded (even without being a scientist). That's basically saying that 1/3 of the suns energy (light) is useless to plants. Beyond that you would be saying that one third of the suns light is actually harmful to plants. But in fact, plants have evolved over billions of years, and have adapted to using the suns light very well, and with absolutely no adverse reactions to being exposed to it. In fact there is nothing better for plant growth than natural sunlight (woody plants or not). So ya, I would love to see the creditable evidence that supports otherwise. Creditable meaning from independent research departments, not product manufactures or the research that's funded by them.

Don't be fooled by more bands = better results. That's simply unfounded. I have a tri-band 50w panel, and the same panel using quad band + 4500K white. The tri-band had the EXACT SAME PERFORMANCE as the quad-band when it came to the test crops of everbearing strawberries and spinach. I've seen dichromatic panels perform similarly.

Again here I would love to see the creditable research that supports the statement that less wavelengths of light is better. To me that's what's unfounded, and sounds like a product manufactures propaganda. Nature doesn't seem to agree. Again I state "THERE IS NOTHING BETTER THAN NATURAL SUNLIGHT FOR PHOTOSYNTHESIS, AND THUS GROWING PLANTS. That's sunlight, and includes all it's wavelengths of energy (even the green spectrum), and with no adverse effects from it, just thriving growth.

I would also love to see the creditable research results of the side by side comparisons of different plant types, that supports the claims of achieving the exact same results. I'm not talking about white led light bulbs. I'm talking about individual wavelength LED bulbs, covering all the individual wavelengths (covering the full spectrum of natural light), where as a whole will put out a white light. As well as the side by side comparisons of LED's, and high density discharge lights, and for various plant types. Without that, and from creditable sources as I mentioned, there is no legitimate comparison, and just unfounded clams (likely from product manufactures).

I'm bleaching plants from 18 inches away with a 300w panel using true 3w diodes. 2,000umol+ intensity (that's sunlight intensity) from a foot away, unlensed, smashing the outputs of a 400w CMH. If you want to go by the latest, Cree's about to drop a 200+ lux/w white diode out. Currently, we've got 150+ (but that doesn't matter, photon flux density in certain wavelengths matters.)

Also, most LED panels are using research from the 90s, and specifications from the 90s. that 7:1:1 (or similar) ratio is just GARBAGE. It's fine for vegetative plants but for producing fruits and flowers you MUST have more blue for bulk mass production, as it's the higher-energy blue photons responsible for the majority of biomass production. All that red does nothing without the right balance of blue to match!

Sounds like this statment is right out of the pages of a product manufactures web-page. Where is the creditable research that supports this. I know that LED technology is improving, and even slowly coming down in price. But I want to see the creditable research that shows/supports the same growth rates, plant structure, overall foliage and fruiting (in both quantity and quality) is the same or better than with MH and hps. As well as for various plants, including large plants like indeterminate varieties of peppers, tomato's, and/or large vine plants like melons, peas, cucumbers, squash etc. is the same or better using LED's than MH and HPS. As well as using the same amount of light fixtures, and with less wattage/electricity to grow them than with HID lights. Until then, LED's are still no match whatsoever to the light intensity of MH and HPS. It doesn't make them comparable when you need many expensive LED panels to do the same job as the MH and HPS, especially when you want to grow more than one or two plants. LED's run cooler so they can be placed closer to the plants, but that's also a necessity with LED's, making it necessary to have many LED panels to cover the same amount of foliage for larger grows. And if you want more light output, you cant just get a larger wattage bulb, you need a whole new expensive light fixture.

By the time you add up all the wattage from all the LED light panels needed to grow a decent amount of plants using LED's (because of the extra panels you will need for good coverage), it's not nearly as cheep as the light manufactures say. They will say a particular LED panel is equal to say a 400 watt MH bulb, but that wont be true when you go to use it as a replacement for it, and you will need more lighting to make up the difference (weather it be LED or otherwise). At least if you don't want to sacrifice growth results, don't expect that to be true. That's just a sales tactic to sell you a LED light based on cost (electricity) savings. But they wouldn't sell nearly as many if they told you you needed the much more expensive models for that kind of coverage. And again that's just comparing coverage (intensity), and not plant growth and/or health.

A watt is a watt, and it cost the same amount of money power a watt of LED's as it does to power a watt of HID. If you add it all up, there will probably be some cost savings in electricity used with LED's, even when needing multiple LED's, though that's strictly talking cost saving in total amount of electricity used here, and nothing else. That's not comparing plant growth between HID and LED's, and/or the amount of wattage needed from the LED's in order to have acceptable growth results, much less in comparing it to the growth of HID lighting. But regardless of what the manufactures say, you will need many multiple expensive LED panels to do the same job as MH and HPS lights, and/or very expensive large models. Now your grow just got way more expensive as a result. And who wants to wait ten years for the difference in electrical cost to finally make up for, and start paying off after the much higher initial cost.

P.S. Don't get me wrong, I think LED's have a place in hydroponics, and perhaps may even someday be the preferred lighting choice. But they still have a long way to go before they can match MH and HPS, regardless of what the LED manufactures try to sell you on. I'm also hoping to see the costs come down to where they would be cost effective to buy, even if only as supplemental lighting. But I'm not going to shell out $300-$400 for a light to grow a small amount of lettuce based on less electricity, when I can build a florescent lighting system to do the same job (if not better) for about $50.