I'm looking to yeild a pound if possible. Should I go with a 400w and supplement with cfls or go 600w? I have a 4x4 tent with a 6 inch inline fan for exhaust. Also any advice on getting a pound in a 4x4 would be much appreciated.
more lumens more yeild. Personally, i'd go for the 600w and a cool tube or save up and get a 1000w cool tube/aircooled light kit.
I'd be skeptical of a 400w. My 1kw seems to barely (or maybe not at all) be enough to probably light my entire 4x8' tent. If looking for spectacular yields stepping up to 1kw or comparable lighting with cfls would be best probably. As for having your heart set on a predetermined yield and being a new grower (you posted in Beginners) I would probably suggest you only expect to learn things for the first grow. If you get anything smoke-able out of it then Yay, if not well knowledge is priceless. I couldn't tell you if a LBS in that tent with any light/set up is do-able though.
I'd go with the 600 for the reasons listed. 4X4X6 tent? that's what 106 cubic feet? 6 inch inline fan seems a lot for that small space, what about air intake, passive? As A suggestion, why not learn to grow good quality bud first & then grow the lbs. Don't get me wrong. Only been growing for a year & I certainly don't have all the answers. Cheers
A 400 wont cover 4 x 4 well. A pound is very possible With a 600w. I just finished an auto run with a 600 in a 4.5 x 4.5 and pulled around 400g.
How many plants? ive tested lumens in my 4x4 with a 400w, and its the same everywhere great journal for what your looking for http://forum.grasscity.com/indoor-grow-journals/677120-400-mh-hps-4x4-tent-scrog-grow-8.html
[quote name='"dudeodan"'] How many plants? ive tested lumens in my 4x4 with a 400w, and its the same everywhere great journal for what your looking for http://forum.grasscity.com/indoor-grow-journals/677120-400-mh-hps-4x4-tent-scrog-grow-8.html[/quote] Either your test results are inaccurate, or you should document and publish these results because you have just broke one of the laws of physics. http://csep10.phys.utk.edu/astr162/lect/light/intensity.html "The intensity of light observed from a source of constant intrinsic luminosity falls off as the square of the distance from the object. This is known as the inverse square law for light intensity." The grow was seven autos. One was a runt and got only 22g, but the others have ran 56 to 76g. If I knew they were gonna get so damn tall I would have scrogged them and should have been able to hit 1lb dry. There is a link in my sign to the journal. I have been pleasantly surprised considering the bad rap autos get. Not a bad yield for about 70 days from seed in my opinion.
I think that a 600 watt light would be weak in a 4 x 4 tent. If you wanted to do a 400 or 600, you would need to do 2 of them. You could do 2 400s or 2 600s. That way your plants would have a lot of light and they would also be closer to your lights since your light sources would not be so far apart. Rule of thumb is 50 watts per square foot. A 1000 watt light would work, or 2 400s, or 2 600s. I think I would personally choose 2 600 watt lights and get them both with dimmable ballasts. That way you can have the light dimmed down when the plants are small and crank them as you need more area.
indeed i say if you're worried about light coverage with a 600w in a 4x4, just get a light mover and some chain so much easier and literally cooler than running a second lamp
A 600 is better than a 400 but the question is managing the heat. 6" might work depending on how much fresh air you are bringing in and at what temperature. No way you will get a lb off a 600w unless you are a very experienced and skilled grower like joker865.