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How many pots in grow box with 400w lamp?
- Thread starter Agropop
- Start date
Pot size depends on the size of plant you plan on growing. Large plants = fewer pots, Small plants = more pots.
A single 400w lamp is way under powered. You are looking at 21 watts per square foot. You need at least (1) 1000 or (2) 600's or (3) 400's or a combination of the before in the amount of space you have there. Or not use the whole space.
A single 400w lamp is way under powered. You are looking at 21 watts per square foot. You need at least (1) 1000 or (2) 600's or (3) 400's or a combination of the before in the amount of space you have there. Or not use the whole space.
Agro go check out growroom design and the new growers thread. Study, study, study. But you are way under powered for your light in such a large area. My best guess would be 5 or 6 grouped under the light and as close as you can. Read one of the sticky's for new growers lots of them here. Study
Crush
Member
Your light can do about 1m x 1m x 1m. You need to grow something That is short, and make sure to lower the light as close as you can to the bud. The 400w isn't too hot.
You can put more plants in, just shuffle them around a and don't expect miracles. Genetics will determine a LOT of what happens.
You can put more plants in, just shuffle them around a and don't expect miracles. Genetics will determine a LOT of what happens.
Agropop
Member
I knew that I have underrated light for this size of grow box...
But the reason for 400w in 1,4x1,4 is because the extraction fan...noise
If I trun my fan on stage two (probably a must for 600w 350cmh ? ) this thing produces too much noise at the intake and that I cannot afford because of neighbours... The exct fan on stage1 220cmh is loud, but on the stage 2 its catastrophic loud and thats why I dont think on 600w or more...
But the reason for 400w in 1,4x1,4 is because the extraction fan...noise
If I trun my fan on stage two (probably a must for 600w 350cmh ? ) this thing produces too much noise at the intake and that I cannot afford because of neighbours... The exct fan on stage1 220cmh is loud, but on the stage 2 its catastrophic loud and thats why I dont think on 600w or more...
Hi there!
I would like to know what is a reasonable maximum pot number (pot size 25cmX25cmX25cm) that can be used in grow box 1,4mX1,4mX2m, with 400w lamp & ADJW reflector?
Strain would be sensi seeds big bud...
I'd scrap the reflector and hang the bare-bulb vertical. You've got plenty of space to work 6 plants (or more) around the bulb.
Best most fun growing to date was done with a 400w. I used to run 2x2 boxes with a 400w and a 5k A/C...all sealed. I'd put 16, .5 gallon square pots in there, aka a true SOG, 4 per sq. ft. Keep 'em under 22" and you'll have full length colas every time and great smoke.
I say this only because I found the biggest limitation of the 400w system was thickness of canopy and the lights inability to effectively penetrate the lower branches, thus creating more fluff than true mature flowers. Switching to SOG style at such an intense wattage, 100w per sq ft, I had comparable to 1k results. And before I get jumped...comparable, not the same...
dank.Frank
I say this only because I found the biggest limitation of the 400w system was thickness of canopy and the lights inability to effectively penetrate the lower branches, thus creating more fluff than true mature flowers. Switching to SOG style at such an intense wattage, 100w per sq ft, I had comparable to 1k results. And before I get jumped...comparable, not the same...
dank.Frank
ok, wait, your pot size is determined, as is your space...i am COMPLETELY lost as to why you need our help...this is a math issue...a meter is 100 centemeters, and 1.4 meters is 140 centemeters, that means you can fit 25 pots...5 long five wide, using 1.25 meters square...this is a poor way to decide your space...
IMO the correct way to figure this out is by starting at the source: how many watts are you comfortable running? for you that is 400 watts, this covers a 2 by 3 foot space or something like .7 meters by 1 meter, or at the most 1X1 meter, any more than that and your watts per square meter go down and with a 400 you will end up with fluffy popcorn buds, some people call it larf? lol a 400, while a nice little light, doesn't have the penetration power of a 1000 watt or even a 600, so overall your buds will be a little less dense than if you used a bigger light, also the buds will be less DEAP! this means you have less light penetration so your plants will need to be smaller, as only the top 12 inches will be quality buds, if you grew a 5 foot plant under a 400 watter you would end up with 4 feet of stems with a foot of buds on top. this means your plants as a rule should be much smaller than if you were using a light with more pressure like a 1000w.
now that you know the size of the light and the approximate size of the usable floor space, coupled with a general understanding that you want to keep your plants around 18 inches tall at the most, you must decide what type of growing style you want to use, sea of green, screen of green, vertical, bushes, etc. personally, i use a 400w hps and i prefer sea of green, i feel it's the most efficient way to use the limited penetration of the light whilst maximizing yield. they all have benifits and downfalls, for instance, sog requires a much higher plant count than normal, and it is preffered to start with clones, if using seeds i tend to use a sort of minibush/sog style, with less plants per square foot, but more veg time. traditional sog is around 4 plants per square foot with 0 to 1 week of veg time, from clones of ONE PLANT. for my example we will say that is your choice...
now you know what light you want, the size of your foot print, and the size of the plants. at that point you can pick out pot size and plant number. with a 2X3 foot growing footprint, you have 6 square feet, at 4 plants per square foot that gives you 24 plants, obviously you would want 6 inch pots, half gallon grow bags, or something else small that you could pack in the area, and if your growing other styles your pots must fill the footprint as well as possible, to maximize root space, you don't want a lot of room between pots, better to use bigger pots than to use smaller ones with big gaps in between pots, imo, even if the plants don't use all the space...
this is what i usually recommend to people trying to decide how many plants to put under a light. EVERY grow room is different and every grower is different, results will vary and you must find what works best for you. i would research the different grow styles, because that is a major factor, and keep in mind, when you do, there are a lot of people that consider their way to be the best way, but in reality they all yeild fairly similar if grown right.
also none of this matters if you are set on using your 1.4 meter space with 25cm pots, if that is the case, the answer is simple, 25, lol
p.s. sorry i realized i switched back and forth between metric and imperial numbers, but i was in a hurry and didn't feel like converting it all after the fact
IMO the correct way to figure this out is by starting at the source: how many watts are you comfortable running? for you that is 400 watts, this covers a 2 by 3 foot space or something like .7 meters by 1 meter, or at the most 1X1 meter, any more than that and your watts per square meter go down and with a 400 you will end up with fluffy popcorn buds, some people call it larf? lol a 400, while a nice little light, doesn't have the penetration power of a 1000 watt or even a 600, so overall your buds will be a little less dense than if you used a bigger light, also the buds will be less DEAP! this means you have less light penetration so your plants will need to be smaller, as only the top 12 inches will be quality buds, if you grew a 5 foot plant under a 400 watter you would end up with 4 feet of stems with a foot of buds on top. this means your plants as a rule should be much smaller than if you were using a light with more pressure like a 1000w.
now that you know the size of the light and the approximate size of the usable floor space, coupled with a general understanding that you want to keep your plants around 18 inches tall at the most, you must decide what type of growing style you want to use, sea of green, screen of green, vertical, bushes, etc. personally, i use a 400w hps and i prefer sea of green, i feel it's the most efficient way to use the limited penetration of the light whilst maximizing yield. they all have benifits and downfalls, for instance, sog requires a much higher plant count than normal, and it is preffered to start with clones, if using seeds i tend to use a sort of minibush/sog style, with less plants per square foot, but more veg time. traditional sog is around 4 plants per square foot with 0 to 1 week of veg time, from clones of ONE PLANT. for my example we will say that is your choice...
now you know what light you want, the size of your foot print, and the size of the plants. at that point you can pick out pot size and plant number. with a 2X3 foot growing footprint, you have 6 square feet, at 4 plants per square foot that gives you 24 plants, obviously you would want 6 inch pots, half gallon grow bags, or something else small that you could pack in the area, and if your growing other styles your pots must fill the footprint as well as possible, to maximize root space, you don't want a lot of room between pots, better to use bigger pots than to use smaller ones with big gaps in between pots, imo, even if the plants don't use all the space...
this is what i usually recommend to people trying to decide how many plants to put under a light. EVERY grow room is different and every grower is different, results will vary and you must find what works best for you. i would research the different grow styles, because that is a major factor, and keep in mind, when you do, there are a lot of people that consider their way to be the best way, but in reality they all yeild fairly similar if grown right.
also none of this matters if you are set on using your 1.4 meter space with 25cm pots, if that is the case, the answer is simple, 25, lol
p.s. sorry i realized i switched back and forth between metric and imperial numbers, but i was in a hurry and didn't feel like converting it all after the fact
Crush
Member
He can grow under a 400w in his room. Reflective walls are over rated. It's so important that he finds a pheno that puts on rock hard nugs. I have one plant that's a freak.. the nugs are just crazy hard. You can grow that thing under a 60w light bulb and I'll bet you get nugs.
With tall sativa plants, it won't do well under the 400.. the buds will be airy.
I also agree with the guy that said to use the bulb down the middle. That's what I would do in his situation. If he has the right plants, he'll do real well.
With tall sativa plants, it won't do well under the 400.. the buds will be airy.
I also agree with the guy that said to use the bulb down the middle. That's what I would do in his situation. If he has the right plants, he'll do real well.
Gotta disagree with you here on the basis of physics. Not saying you can't get something done without the walls... but lets just look at an example.
Go into your basement, turn out all the lights and flick your bic. See how well your basement is illuminated by that bic. I mean, you'll be able to see an area around the lighter, but it'll quickly get murky and I doubt you'll see the other side of your basement well enough to navigate.
Now stick your bic inside a small box and flick it again.
Everything's all lit up and you can not only make out shapes, but colors and shades and even read text.
The light in the box is bouncing back off the walls of the box which are much closer to your light source. The light in the basement has to travel much further and loses intensity rather quickly.
If those walls are reflective, your color perception, depth perception, etc. will be enhanced. If those walls are flat black, it will be less so (but still much better than the view of the whole basement.)
I'm not saying you'll see the same difference by putting a 400w in a 2ft space or a 4ft space, but a meter would notice the difference and the physics would be the same.
Crush
Member
I own a light meter and have tested all around the walls and such.
What I found is, the smaller the area (like a grow cabinet in a very small space) the reflective walls mattered more. But if you are talking about a whole room and such. I didn't find much of a difference. It doesn't make a difference for my 3.5 x 3.5 space. Look at any of the 10k watt grows and no ones using reflective. Even on the greenhouse seeds video.
What I found is, the smaller the area (like a grow cabinet in a very small space) the reflective walls mattered more. But if you are talking about a whole room and such. I didn't find much of a difference. It doesn't make a difference for my 3.5 x 3.5 space. Look at any of the 10k watt grows and no ones using reflective. Even on the greenhouse seeds video.
By the time you're using 10k watts and all the assorted bells and whistles that come with it, the amount of weight you can get by adding reflection might not be worth your time.
When you're growing with a 400w bulb, my aim would be to maximize light and soak up every watt.
For ~$40 I did my entire 2.5'x6' room on all the walls and ceiling with reflectix. Besides light diffusion, it also insulates against heat.
Marquis de Sod
Member
i got mylar, and my 4 is on a mover. @ 5 ft, 6"x6" pots about six on each long end, and 3-4 across. still,... this is just a warm up for the 1kw hps. might as well be in a phototron otherwise,, 400W just hasnt got any balls. i just use it to get the gals into bloom cause i got too many. when i get under the limit, or have other 1K room, the 400's going back into mothballs, where they belong. peace
Marquis de Sod
Member
if a mover is out, they sell these lite dispersers, that push over the lamp base. it's spozed to prevent hot spots too. that is only in horizontal tho, i switched to vert. i think it's better, gives you more plants i think than horizontal lamps with reflectors. might not matter all that much if you strip the plants tho. just seems to me i have about 4 more plants in vert than i did in hor., and doing better as well.
Hmm...Reflective walls in a small space are extremely useful. If you can make it so that say 8k lumens bounces off a reflective surface and only dissipates to say 7.5k lumens, wouldn't that be better than hitting a non-reflective surface and being drained down to 5.5-6k lumens? Also, it's not always the strain/pheno that dictates the outcome of a crop. If you just plain ol' don't know how to take care of a plant by having the light too far, too close, too many, or not enough nutrients...you're not going to get the biggest bang for your buck. 60w...that's something I would love to see someone attempt. I'm sure you can get something that resembles bud, but it won't be anything to talk about. If you can get a decent harvest using a single 60w even with a single plant, I'd shove my foot so far down my mouth I'd never talk again.
Crush
Member
Yeah I agree that reflective walls work in very small micro grows and tiny spaces where lights are fixed above. I have tested with my light meter in these areas.
But the rest of your post I disagree. In most rooms it doesn't do much and is over rated. Not enough to seriously effect the yield of your grow. I would say that reflective material on most grow rooms is not 'mandatory' for anyone to be able to grow.
Also, you say the strain doesn't dictate the outcome of the crop. I again I totally disagree. As long as it's getting fed and has light, the pheno can either produce, or it won't. Telling new growers that there's anything they can do to get blood from a stone is just false. It's impossible.
Agropop
Member
Hi, for your time... U gave me a good idea with this vert grow and with fan under, which I will deff try, and with lst 
For veg Ill use 400w mh, and If temps will not be to high, Ill use for blooming 600w hps...
The walls in grow box are white, but I have mylar foil and I think Ill use it anyway
for your time... U gave me a good idea with this vert grow and with fan under, which I will deff try, and with lst For veg Ill use 400w mh, and If temps will not be to high, Ill use for blooming 600w hps...The walls in grow box are white, but I have mylar foil and I think Ill use it anyway
Bass Akwards
Member
Try a CMH Setup
Try a CMH Setup
Check out this thread:
http://www.icmag.com/ic/showthread.php?t=72215
A 400 watt CMH has great light output, and low heat.
They retain 85% of the lumens, compared to 64% for MH/HPS.
In a small space, with white painted walls, decent ventilation, and a few small oscillating fans, you'll do just fine.
CMH bulbs can be placed much closer to the plants, and put out a balanced spectrum.
They also give off UV-A and UV-B, so wear dark sunglasses.
Try a CMH Setup
Check out this thread:
http://www.icmag.com/ic/showthread.php?t=72215
A 400 watt CMH has great light output, and low heat.
They retain 85% of the lumens, compared to 64% for MH/HPS.
In a small space, with white painted walls, decent ventilation, and a few small oscillating fans, you'll do just fine.
CMH bulbs can be placed much closer to the plants, and put out a balanced spectrum.
They also give off UV-A and UV-B, so wear dark sunglasses.
