Backyard Aquaponics
A place to discuss aquaponics

I have been researching the use of LED grow lights for some time and am becoming very excited with the possibility of being able to provide a much fuller spectrum of light while consuming much less energy. Currently, no fixture available suites our needs within a reasonable price so we intend to make our own. We have skilled engineers who can design fixtures to match our NFT set ups. I am curious as to if anyone here has tried LED and compared them to T8 or T5 set ups and you could share your experiences.

Haven't used them for plants ,, but did invest in some to use for my house lighting.
My opinion ,, yet ANOTHER over-rated greeny driven piece of crap.. rated similiar output to a 50 Watt Halogen but only use 3 Watts ,, BULLTWANG ,, VERY little light comes out of them.
I believe the Luxeon led's are better ,, but still expensive.

I have been looking into CREE which has some very impressive high output leds. Here's a link to one manufacturer using their LEDs for grow lights. I would be buying the CREE LEDs directly and building our own fixtures. There is a big difference in high output LEDs and the ones available at the home improvement stores.

http://www.homegrownlights.com/diycree.html

Kinda like with the early Florescent lamps, the currently available LED lights are not quite up to the task yet and they are over priced. With time I'm sure better ones will be developed but we are not quite there yet with anything I've seen available.

I work in Entertainment where new LED lighting is being used extensively but it still has limitations.

I agree with limitations, but remember there are many different variations and qualities of the product. The flexibility of size and being able to design and build our own fixtures ranging from 2,100K to 6,500K in the same 5x5" fixture is what's exciting compared to flourescent. I was hoping someone had tried them for growing rather than trust web results.

I've been experimenting with LED's and also Fluro grow lights.

On the fluro side I got the AeroGarden which has 2 compact fluro's, they work REALY well. Chillies and tomato's went wild.

I then tried a running a simple hydro setup under cover with only indirect light, very poor results and all the plants were lying on their side trying to find some light. Installed a cheap 225led RED/Blue light from ebay and had some initially promising results in that all the plants immediately stood up straight and headed for the LED's plus started to grow. However the growth wasn't anywhere need as good as the fluro's but considering that the LED array was less than 10watts it did have some effect. I would say the LED's DO have a beneficial effect but you can't go elcheapo, you need at least 15-20Watts per Square foot, still less power usage than the fluro's and far less that the other options but a lot more expensive initial investment. Considering their lifespan I would say in the long run you would be better off with the LED's as long as you got good high power. Also don't use the white Cree LED's. The major benefit with LED's for plants is that all the power they emit is in the wavelengths that the plant needs, if you use white you are wasting what little power you have in unused wavelengths, far better off with high power red and blue LED's.

That was what we were thinking. Multiple Blue, Red, Orange all in a 5x5" panel, one over each plant spaced 8" on center in each grow channel.

This is the one I got. Basically fine but a bit too underpowered, total power 13.8 Watts, by the time you account for losses in the driver circuits etc your talking around 10Watts for the lights, not realy enough.

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 0412592453

Move op to the next size and I thing it would be quite good, put it on a chain so that you can get them really close as seedlings and then lift them up as the plants grow to maximise the light hitting the leaves.

Oh and don't bother with orange. Just Red/Blue. Also if you really want to get technical you can use more/less of one colour. Can't quite remember which colour is for what but one gives stem and leaf growth and the other flowering so depending on what plant you use you can adjust the light to reduce or promote flowering.

We were thinking of reverse engineering something like this for each plant and mounting all into one fixture with our spacing.

http://www.homegrownlights.com/14wled.html

Blue for leafy greens/Red for flowering stage. The other nice thing as you mentioned is that we can customize the amount of spectrums depending on what plant is needed, and if we make the whole fixture modular ie. plug and play, we can change them out per fixture location depending on what we want to grow.

The general thought in professional growing is that you must use both led's and florescent to grow plants. I dont think they have nailed down all the light frequencies just yet. Truth is its very early for that type of thing. Its going to require a larger range of frequency that is currently manufactured in LEDs. If you build your own led arrays they can be very cheap, but it takes a lot of time and they seem to work with lettuce.

Everything seems to work for lettuce. I have friend who is successfully growing tomatoes and peppers inside using LEDs however, they are in pots with soil. They look pretty impressive though and I know for a fact he started them from seed. He is only using red and blue with the majority being red.

If you have to grow indoors you might as well used leds to save some power.

That is our strict limitation so we'll have to make something work. Wish there was more info (diffinitive) on the topic though. Guess we'll have to write the book.

There is a thread some where on this forum that covers all you need to know for LED plant lighting: intensity, distance, wavelength ect..