That's a huge amount of light for covering 4'x2'. Useful for real full sun plants, probably not too many hours a day, and it might be helpful if you could only run half the tubes except for a few hours in the middle of the day. I guess you don't have the option of raising the lights and covering a larger area ;)

Why the tent? If you want to have the lights inside the tent, I think everything will melt. You'll probably need a fan anyway to stop the leaves scorching under all that light.

my bad the tent is 4x4x6.5 and the tent is flame retardent, i got a fan also

Your 8 tubes total about 432 watts. For less money, you could have gotten a 400 watt ceramic metal halide horizontal and that would cover almost 2x the square area and up to 2.5 feet vertical (as opposed to one foot vertical with the t-5s)

You might consider a 250 watt cmh. The tent enclosure is counter-productive to plant growth, because it concentrates the heat and make ventilation more difficult.

With your t-5 fixture, you have a choice of either 3000 Kelvin (red) or 6500 Kelvin (blue).
cutting stage: half/half
most of growth stage: all 6500 Kelvin
last week of growth stage: half/half
(this is to reduce excessive accumulation of growth hormones which would cause excessive stem elongation in the first week of bloom)
most of bloom stage: all 3000 Kelvin
last week of bloom stage: all 6500 Kelvin

wow where can i get a 400 watt cmh for 220, and thats after shipping?

I think the best source for cmh is Hydro-Tech:
www.hydro-techn.com

I assume you mean 220 volts. With that you should
get a 240 volt timer. Hydro-Tech has that also.

The best temperature is 76F. Remove the plastic
from the hydro-hut and you will see an immediate
drop in temperature and probably higher humidity.
The best relative humidity is between 48 and 57%.

is this guy a spammer or something basically trying to sell me cmh from some website that when i looked for them didnt have them.
but i do plan on running half the lights, and the plants i will be growing need to be in shade, so i was gonna use a filter anyways, just found a cheap deal and the hummity isnt a problem, the more the better.
but wouldnt you say 8 bulb t5ho fixture for $220 dollars is a steal. came with 8 bulbs also, my choice.

Where did you find that fixture for $220? That's a heck of a deal. I've been looking for the same thing and they run around $400.

You asked where you could get a 400w cmh, and I told you. I referred you to the website so you could read the articles there, and give them a call. CMH may not be prominently featured, but it is available there.

If you want the light to cover a 4'x4' area, and your fluorescent reflector is only 2'x4', that wouldn't be enough light in most cases. If your plants need shade from sunlight, that doesn't mean they need shade from artificial light. Just lift your fluorescents up higher if you want less light.

I would remove the plastic from the hut, to improve air circulation and lower temperature. The "hut" is a complete waste of money from the viewpoint of plant growth.

ok i said i wanted something under 230 and the prices where alot more then that jeeze. but theres someone on ebay selling them it was shipped out yesterday ill let u know how they are.
how is the tent a waste of money im in a small place and thats alot of light need to confind it and the tent will be vented with duct fans.

Here is a link that might be useful: light

(college grower) ok i said i wanted something under 230 and the prices where alot more then that jeeze. but theres someone on ebay selling them it was shipped out yesterday ill let u know how they are.

(Lermer) I went to the link. This is advertised as a fixture, probably the bulbs are not included. The bulb spectrum wasn't specified. I recommend getting both 3K and 6.5K bulbs. They usually go for $16 each. If they are not included, that would be another $128 at retail prices. I would get more than 8 tubes, in order to have different combinations for different stages.

I don't know what prices you are talking about, that "where alot more than that jeeze". The 400w cmh starts at $265. That includes the bulb and everything. If the fluorescent fixture doesn't include the bulbs, you would be paying $92 more. 8 tubes at 54 watts each would mean you are using 432 watts. So you are saving neither watts nor money by using a less efficient light than cmh.

wow you must be really tryin to sell those to me, the fixture comes with my choice of bulbs pick 4 3000k and 4 6500k if you would of read it. ive been reading bout chm and from the factory they rate at best 94 lpw there life is almost 2 times shorter, there blue seems to be in the 500+ plus range, but red looks good, but in the long run the t5 depreciation is less then the chm from wat the bulb companies say, im sure chm will get better, but for the price i found my lights at, it seem like a better deal.

and more efficient. the depre value on the best chm is 20% thats alot more then the 9percent t5 have, but lumens arnt good value to measure plant growth. but just anther way t5 are better lol.

You're fine with the lamp that you just bought. Nobody wants a metal halide under their bed, ceramic or otherwise. I'm still curious about the tent, though. How is it containing the light, is it opaque and white or reflective on the inside?

Don't be fooled by the improved colour rendition of the ceramic metal halide. Its "full spectrum" is still very spiky (although marketing material often "tones down" those spikes in graphs they produce), especially the main yellow-green and red emission lines which are pretty close to the phosphor emissions in a triphosphor fluorescent. In the ceramic metal halide those spikes overlay a much wider emission in the blue-green part of the spectrum, where a triphosphor fluorescent has another sharp spike in the blue. Overall, you can compare the "spikiness" of a light source by looking at CRI, which is a measure of the smoothness of the spectrum. Standard triphosphor fluorescents and standard ceramic metal halides have virtually identical CRI values because they have remarkably similar spectrums, hence any claims for performance of must apply to the other. Or you can just look up the graphs on the web. Here are a couple of links to get you started:
http://www.eere.energy.gov/buildings/appliance_standards/commercial/pdfs/hid_lamps/philips_2003f.pdf
http://www.netl.doe.gov/ssl/usingLeds/general_illumination_color_basics.htm

the inside its like a flat white, and its got holes for vent, i got a nice duct fan to keep everything cool and vented.

Metal halide lights, HPS, ballasts, etc., are devices involving high voltage, high power, and high temperature. There is an individual who is trying hard to sell items here with unknow specification, manufacurer, reliability, warrenties, UL ratings etc.
Please be very careful, use your judgement.

dcarch

Ceramic Metal Halide is no more spiky than fluorescents. Color rendering index (CRI) gives only an approximate measurement of spikiness, because it does not say the amount of light at each particular band of the spectrum. The highest CRI bulb is the Life Light 400w Ceramic Metal Halide with e-ballast, with a CRI of 95. The electronic ballast tends to smooth out the spikes.