In article ,
zxcvbob wrote:

Pat Kiewicz wrote:
So this year I had a some extra cash, and the metal halide light
I had been using for lo, these many years was due for a new bulb.
The time was ripe for a radical change.

I'd always been unhappy with the amount of power this used and
the dangerously enormous amount of waste heat it created. Due
to all the heat, my tomato plants generally grew too tall too fast
and all the plants were always prone to wilting and water stress.

My plant set up is a three-sided 'light box' lined with mylar and
draped with a half-length mylar sheet on the open end. I use
an oscillating fan blowing in on the plants (and had another on
top of the light trying to keep it cool). I typically grow up to
40 plants in re-used 32-ounce yogurt tubs (arranged in staggered
rows for maximum density).

This year I decided to go high-tech, and did a bit of research and
some fairly serious spending.

My set up this year used two LED light fixtures. The main light
source was a LightBlaze 400 LED grow light roughly centered
in my light box. Behind it I hung a second LED light fixture,
a GlowPanel 45.

I still used the oscillating fan blowing into the box, but as
everthing was running so much cooler, I laid another sheet
of mylar across most of the front of the box.

I'd have to say the whole thing was a sucess. My tomato plants
are much shorter and more robust looking, as are the peppers
and eggplants.

It was strange how black the plants look under the LED lights,
but that is a sign that most of the light was actually being
absorbed by the leaves and very little was being reflected, which
is a good thing.

The weirdest thing to get used to was how odd *the rest of the
world* looked after fussing over the plants a bit; everything took
on a distinctly green after-glow.

The LightBlaze 400 puts out more light than the GlowPanel 45.
and is easier to hang and adjust, but I think if you put together
several GlowPanel 45 grow lights you could get the same results.

LightBlaze 400:
http://www.superled.net/ledgrowlights.html

Sunshine Systems GlowPanel 45:
Available from Amazon.com and other sources.



I wonder if a person who was handy could add a row of these red LEDs
to an existing 2x4' fluorescent "troffer" fixture? Just need to red
ones because fluorescents give off plenty of blue already.

http://www.superbrightleds.com/cgi-b...ispPage&Page2D
isp=%2Fspecs%2Fr3_specs.htm

They could be powered by an old laptop power supply (typically 20V
and maybe 90W)

I may need to ask about this in the sci.engr.lighting froup.

Bob

Why not just get 3000° K fluorescent lights?
--
- Billy
"Fascism should more properly be called corporatism because it is the
merger of state and corporate power." - Benito Mussolini.
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