just got a new box, wondering about size of light I need

So I just got an old entertainment center/armoire deal. It is roughly 5x4x2 (HxLxD). I understand that the optimal light for that area would be around 400w? Yet I am worried about the heat buildup that would come from a light that size. I have read about people saying your buds will be too loose with a 250w in a 2x4 grow area, but I also see that a 250w is recommended for 3x3 which is a larger sqft than what I have now. I guess my question is if I am just trying to grow 2-3 medium sized plants wouldn't 250w be sufficient in this area? Also does anyone have a similar sized grow area and what do you recommend for light/exhaust?

A 400 would be nice if it was a sealed air cooled hood with proper ventilation. If not, then you should consider a smaller light.

thanks for the quick response Tommy +rep to you!!! Do you recommend any sealed hoods? I have been searching I see a lot of air-coolable but not a lot of choices for sealed hoods.

I second tommy's suggestion. Run a 400w at least. I personally wouldnt go any smaller for that area, just make sure you have real good ventilation.

why not get a 600w dimmable ballast?
I see a lot of people on here running 600s in a 2x4 space.
dimmables you can turn down to like 60%/75% and 100%.
So if you run it and it's too hot, you can just turn it down a notch.

You know you're going to upgrade someday, so I wouldnt buy a 400.


For your question about the hoods:
Daystars are affordable, so are Xtrasuns.
The difference between aircooled and not would be vents vs ducting holes: see pics
vented:http://www.afgrowsupply.com/xtrasun-white-reflector-air-coolable/
aircooled & sealed: http://www.afgrowsupply.com/xtrasun-6-air-coolable-reflectors/

So in regards to your question about a sealed hood that's not air cooled, you would want a vented hood. There's a glass pane that stops some of the heat from hitting the plants, but it's not actively cooled. The hear just dissipates out of the vents at the top.
I'm not sure that the first link includes the lens, they might sell that separately

Yeah, I run one of each. The sealed vented hood is in a larger space where heat is not an issue, the vented hood is in a smaller space and keeps the area cooler. Make sure your choice has tempered safety glass, safety first.

rollinstoners said:

So I just got an old entertainment center/armoire deal. It is roughly 5x4x2 (HxLxD). I understand that the optimal light for that area would be around 400w? Yet I am worried about the heat buildup that would come from a light that size. I have read about people saying your buds will be too loose with a 250w in a 2x4 grow area, but I also see that a 250w is recommended for 3x3 which is a larger sqft than what I have now. I guess my question is if I am just trying to grow 2-3 medium sized plants wouldn't 250w be sufficient in this area? Also does anyone have a similar sized grow area and what do you recommend for light/exhaust?

Click to expand...

My closet is appx the same size as your cabinet will be ... I will be using a hydroponic grow system for (6) seedlings/plants ... I plan on using a 150 Watt SunSystem unit with a 400 watt MH Bulb as well as (2) cfl clamp-on's for side lighting each with a 6500k lumen output. This is only for the veg cycle, as I am planning on building a seperate flowering unit in the room. I will be coming along for the ride on this thread to see if we both can learn from some seasoned vetereans out there Hope this helps my friend

HPS lights throw an oblong light pattern w/ less light coming from the ends so mount it horizontally w/ the base at the back or front and the sides facing the longer area. since you are only planning 3 plants& only have 5 feet of height, you probably wont use all 4 feet wide.I would consider a shelf on one side w/ a reflective curtain to make the grow chamber 2x3. it would be better for a 250 watt light & give you a place to store all the paraphernalia that goes w/ a grow.

Thanks for all the replies folks, I upped all your reps. Thats funny mrmadcow I was laying in bed last night wondering which way I would hang the light for it to be most effecient. I was planning on having it exhaust from the sides but now realize I should mount it to the front and have it exhaust thru the back of the box. I am now leaning more towards a 400w or possibly a 600w dimmable like Dennis sugguested. Then if it is running to hot at least I could always switch down to a lower %. I am just working on a really tight budget right now, just got a new job waiting for a check and trying to pay off some credit card bills at the same time. Maineyankee good to hear you will be following and I hope we both can learn a lot here!!!

If budget is a concern, I would go with the 400, it will serve you well until you expand your grow. It doesn't make sense to pay for a 600 if you are going to have to dim it.