lighting Lighting Options for Covering a 4x4 Area? LED T8 Replacement Bulbs?

I am already running a 400-watt HPS for one 4x4 area, and want to add another 4x4 area.  These areas are/will be used for the pre-plant out growing stage, only.  Excluding another 400-watt HPS, halide, or LED set-up, what options do I have?  I already have 3-dual ballast T-8 fluoros on hand, and want to use them.  Would I need to supplement them?  Thanks.  
 
EDIT:
 
Any experiences with LED T8 replacement bulbs?  Is the technology here, yet? Will the plants grow faster/larger?
 
juanitos said:
usually for 4x2x2 area u need 4 bulbs of t5 or t8.
 
you can use cfls if you don't want to use the tubes, see here for spacing.
Do you know how many watts each cfl is?  They look to be about 16"-20" apart.  I guess those are standard seed tray.  Maybe I can contact Mike McDermott.  Thanks.
 
If your planning just useing the area for starter plants (6" inches or so and shorter), T8 shop lights will work fine.
 
Terravexti said:
If your planning just useing the area for starter plants (6" inches or so and shorter), T8 shop lights will work fine.
Yeah, I want max growth indoors since my outdoor growing season isn't the longest.  I guess the bottom line is, can I get comparable growth to 400-watt HPS from another type of light, for less $$ on my electric bill?
 
Roguejim said:
Yeah, I want max growth indoors since my outdoor growing season isn't the longest.  I guess the bottom line is, can I get comparable growth to 400-watt HPS from another type of light, for less $$ on my electric bill?
 
As I understand it, that's about right.
 
Roguejim said:
I am already running a 400-watt HPS for one 4x4 area, and want to add another 4x4 area.  These areas are/will be used for the pre-plant out growing stage, only.  Excluding another 400-watt HPS, halide, or LED set-up, what options do I have?  I already have 3-dual ballast T-8 fluoros on hand, and want to use them.  Would I need to supplement them?  Thanks.  
 
EDIT:
 
Any experiences with LED T8 replacement bulbs?  Is the technology here, yet? Will the plants grow faster/larger?
I use 9 x 24 watt cfls in my wardrobe  which is 2x4 and it worked really well.if you doubled it for you 4 x 4 space that would work out at 430 watts so you would be better of using the 400W HPS
A 400W hps puts out 50000 lumins.It would take 31 x 24w cfls to get the same amount of lumins at 744 watts of power.
I would go for another 400W hps
 
I agree on going for another 400W HPS/MH. They always give you the best bang for your buck. Better light penetration is going to be key if you are packing a high number per foot, or growing them to be a bit taller before setting them out.
 
I always end up dissapointed by flouro's once the plants get 12-16" or so tall. I love my T5HO bulbs for getting this going for the first two weeks to a month, but after that I take them out to the greenhouse because growth picks up much more quickly.
 
But, nothing compares to the sun if you can use it, as far as power, spectrum, and direction/angle of light.
 
you can get 65k grow bulbs for a t8.
2ea 4' x4,6 or 8 bulbs will do you just fine, as you already have the fixtures.
A bit shy if they are 2 bulb fixtures and you use all 3, but possible if you are meticulously regulating the distance from light to plants.
 
More light fixtures is better if you are growing several types, as some grow tall faster than others.
 
I have Goat Weed, Aji Pineapple and Peruvian Wild that are double the height of my Chinenses.
 
The fastest growth I experience are on the shelves under florescent where HPS kind of overlaps.  Next best is where metal halide and hps overlap.  I -think- hps sepctrum is not the best for veg. growth.

On LEDS, I believe they are superior in every way but I am not bright enough to figure out which ones are best and which are bunk.  Thinking they are still up front expensive but save in the long run.
 
I havn't tested this yet... but i have an idea.
 
Most grow lights with full spectrum etc, consist of white leds, red leds and blue leds. Problem is that blue and red leds are quite inefficient. The red and blue led technology is ~2-3 years old. White leds are getting increasingly more efficient. And when you look at the spectrum of the different cold white, natural white and warm white leds, they atually look quite decent, with continuous spectrums that are not too far off compared to the photosynthetic absorption spectrum. The most efficient led atm is the Cree XP-L led which produces on average 122.6 Lumens/watt at 85 degC. However they are quite expensive.
 
 
I've compiled an image by overlaying a HPS spectrum, led spectrums and the photosynthesis spectrum in word so...erh..yeah. Needless to say its not that pretty.
 
But you get the point i think. If not, the point is: Natural white led's win. In my opinion...
 
155qu1g.jpg

 
The rainbow colored spectrum corresponds to HPS. The blue, green and red lines correspond to cold white, natural white and warm white Cree XP-G2 leds, and the dark green dashed line corresponds to the photosynthesis absorption spectrum. 
 
Another point to make is that the so-called penetration depth (of light ;) ) depends on the light intensity. The closer a given set of leds come to eachother, the higher the intensity.
 
So my claim is: Multi-chip led lights composed of new efficient natural white leds, will outperform those led grow light panels of similar wattage for the reasons stated above, and re-iterated here below:
 
1: more lumens / watt
2: higher intensity
3: better or similar spectrum
 
edit: another point to add:
4: cheaper .....edit2(i mean, cheaper than grow light)
 
I just recently bought such a led light. I have not recieved or tested it yet, and i can find no "grow test" of it anywhere, so it might be a very bold claim to make. In any case, i think its worth a test.
 
Cheers :)
 
If you want to run HID for just starting them out I would look at ceramic metal halide or even just metal halide over HPS. CMH provides a much more even spectrum at roughly 20-40% spectral intensity. So considering that you get a hell of a lot more out of a 400W CMH than you do a HPS looking at the spectral intensity charts. Honestly T8's would be plenty sufficient for just starting them out. If you are comfortable with electronics the most efficient would be ~200W worth of fairly evenly spaced white COB LEDs. Where they get really pricey is the drivers and the electronics for them, which is cheap if you can do it yourself.
 
~Cheers, can't really go wrong as long as you are giving them some light
 
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