Suggested light layout for this size room?

[RandyL]

I might have a new room available for growing. It measures 10 by 12 feet with an 8 foot ceiling.

I'd put in a couple 600 or 1000 watt MH or HPS's, but I want to try the new Ceramic Metal Halides this time. Since they aren't available in anything over 400 watts yet, I was wondering if I'd need 4 of them equally spaced in the room, (like this: ==) or might 2 or 3 be enough to get by on without running the plants short on light?

If I went with 3, I'd try to space them with 2 on one side and the 3rd on the other, positioned in the middle of the room, betweem the other 2.

Pattern for 3: -_- .

 

[Screwnuts33]

Randy,
Really depends on how many plants you are planning. As you know though, the more light the better.

 

[PitViper]

I might have a new room available for growing. It measures 10 by 12 feet with an 8 foot ceiling.

I'd put in a couple 600 or 1000 watt MH or HPS's, but I want to try the new Ceramic Metal Halides this time. Since they aren't available in anything over 400 watts yet, I was wondering if I'd need 4 of them equally spaced in the room, (like this: ==) or might 2 or 3 be enough to get by on without running the plants short on light?

If I went with 3, I'd try to space them with 2 on one side and the 3rd on the other, positioned in the middle of the room, betweem the other 2.

Pattern for 3: -_- .

the biggest reason to run multiple lamps is to increase the amount of light sources. Ideally you want overlapping sources.
4 400s are better than 3 600's
2 600s are better than 1 1000
etc
If you have the money to buy multiple lamps then take advantages of what it gives you in return.

 

[RandyL]

Based on the size of the room, and the layout of my current, smaller grow room, I should be able to fit 40 plants in there in 3 gallon buckets. 2 rows of 8 down one side, a walking space in the middle, and 3 rows of 8 on the other side.

The room is fed by 2 15 amp circuit breakers, one controls each side of the room's outlets. I was in there with a small lamp today and checked it all out.

Each breaker has 2 outlets. 2 on one side of the room on one circuit breaker, and 2 on the other side on another one.

I'm thinking 4 400's would be best, what really annoys me is that 400 watt ballasts don't seem to be much cheaper than 1000 watt ballasts.

The room does have its own A/C unit though, so temperatures should be easy to control. And a window to get the hot air out.

 

[Hogdady]

Based on the size of the room, and the layout of my current, smaller grow room, I should be able to fit 40 plants in there in 3 gallon buckets. 2 rows of 8 down one side, a walking space in the middle, and 3 rows of 8 on the other side.

The room is fed by 2 15 amp circuit breakers, one controls each side of the room's outlets. I was in there with a small lamp today and checked it all out.

Each breaker has 2 outlets. 2 on one side of the room on one circuit breaker, and 2 on the other side on another one.

I'm thinking 4 400's would be best, what really annoys me is that 400 watt ballasts don't seem to be much cheaper than 1000 watt ballasts.

The room does have its own A/C unit though, so temperatures should be easy to control. And a window to get the hot air out.

4-400s wont do it. you have 120 sq ft and 40 plants will fill it. at a minimum of 50 watts per foot, you need upwards of 5kw. 4-1000s on a light mover will give you that because you can multiply your wattage by 125% to 140% on a mover. 30 amps won't be enough unless you can go 240vac. 40 plants need alot of light......

 

[Weed420]

It will also depend on which hoods you use too. if you ise the inline cooling hoods it will take more lights than a 4ft parabolic. I would go with 600's if you can. They are the most efficient with less heat. Once you step up to 1000's you really start dealing with heat issues. Do a good job of looking at what you're going to need in the way of ventialtion and get that setup before you do anything else.

 

[Hogdady]

It will also depend on which hoods you use too. if you ise the inline cooling hoods it will take more lights than a 4ft parabolic. I would go with 600's if you can. They are the most efficient with less heat. Once you step up to 1000's you really start dealing with heat issues. Do a good job of looking at what you're going to need in the way of ventialtion and get that setup before you do anything else.

so how many 600s will he need for 40 plants in a 120 sq ft room?

 

[The Big Man]

400 watts just will not do it unless you plan on having a lot more than four. Even though I use 1000 watt lights, 600 watt are the best.

 

[Tokensmoke10]

Hog, have you considered splitting up the room into a 2 or 3 part room for clone + mothers (optional), vegging and flowering. This would allow you to use less watts on a HPS for the flower part (controlling heat) and T5's for everything else. Shouldn't be too hard to do if ya have some knowledge or something with knowledge about putting up drywall.

 

[Weed420]

so how many 600s will he need for 40 plants in a 120 sq ft room?

I would either go with 2 600's with a light mover or maybe 3 600's if they're stationary. More light is always better but eventually you start running into heat and electricity consumption issues.

 

[Bandit420]

An optimal lighting set up for that room would be 6 400 watt lamps daisy chained for heat removal. Dutch studies over a decade ago proved that it was more efficient with greater yields to light a commercial crop with more 400's over fewer 1000 watt lamps but those studies were also for sog applications. Thats also where alot of the weight per watt target numbers came from.

 

[Hogdady]

I would either go with 2 600's with a light mover or maybe 3 600's if they're stationary. More light is always better but eventually you start running into heat and electricity consumption issues.

thats only 15 watts per square foot....are you sure that's enough?

 

[Weed420]

I have done grows with T5's, 400's,600's and 1000's and to be honest I have never found a great difference in quantity between them. The 1000 seems to be better for making stacked and tighter buds but then you start dealing with the high heat issues which will hurt production. If it was me(money's always an issue with me) I would start at 2 or 3 600's and see how you do. You can always add on more. All grow rooms are different and require different systems to get done what you want to get done.