Is my space tall enough for 250w hps?

MorroN

Well-Known Member
Hi guys, looking to move my next grow into my closet and am wondering if can put a 250w hps lamp in there instead of using the 200w of cfl I have now. Anyway the closet has has shelves 35 cm apart, 60cm deep and 40cm wide and Idealy i only wanted to take out 2 or 3 shelves giving me a height of around 70-105cm but can go up to about 1.5 meters if I have to (i'll just have to move my stuff). Im in student accommodation so cant really start chopping up their furniture, i think they'd get suspicious at the end of the year;)



Anyway, im worried about a few things:

Height, is it gonna be high enough mounting the lamp on the roof of it, will it burn my plants?

Ventilation, without cutting a hole in it, what are my best options? I can leave the other door open slightly and get an exhaust fan at the top and an intake at the bottom easily enough. also what is the heat like off a 250w hps? does most of it come from the bulb or the ballast? the system has a remote ballast so I can mount that outside of the closet easily.

obviously the whole things gonna get smothered in mylar etc.

Thanks:)
 

tellno1

Well-Known Member
with no way to vent ... think hot very hot .... bulbs and ballast give off heat but mostly the bulb ...
 

massah

Well-Known Member
why not just pickup a sheet of plywood and build a small box to put next to that cabinet instead? That way you can cut holes in it for vents+fans, and dont forget if you have anyone near by that would have an issue with the smell...you want to filter it...you can build your own small carbon filter out of loose carbon + pantyhose + metal pencil/pen holders :)
 

zvuv

Active Member
Your height is a bit tight but it can be managed with careful cultivation. You have about 3', the pot needs about 9", the lamp with an air gap under it needs about 12", so you have about 18" left for plant height. Most indicas grow between 18" - 24" so it is doable. You wont be growing a sativa in there, I don't think. You will have to think carefully about the vegetation period and then canopy control by pruning and training.

Your big issue , as tellno1 says, is heat. 250W of cfls or HIDs will quickly raise the temp to 100+ if the heat isnt managed. Leaving a door open with a fan blowing works fine until someone walks into the room or until you need to flower at which point the plants need 12 hours of complete darkness every day. If you can stay on schedule, you could close the door when the lights go out during flowering but MJ plants are very sensitive to light schedules during flowering and if you miss a dark period, it can screw up the plant.

Why not go to the thrift store and buy a cheap cab that you can modify as you wish?
 

MorroN

Well-Known Member
Thank you for the replies. Im growing autos on a 20/4 schedule so keeping a door open wont be a problem, also as long as im not in the room the room door is locked and no one can enter without my permission.

Alright so maybe 250w is slightly overkill. Im trying to find a 150w system, would this help in anyway or will the heat being given out be way too high?

Ive had a thought, I could run some ducting and inline fan from the reflector out of this gap and out of the left hand door. The rest of the gap could be easily masked with some mylar to minimise light escape/entry with a gap in the mylar at the bottom for an intake fan.

As for building a cab, I dont have any tools with me here or any means of getting lumber to and from my room without arousing suspiscion, im on the 11th floor and as i've said its student flats so there are staff around that would notice weird activity.
 

frmrboi

Well-Known Member
as you can see it's do-able if you can deal with the heat. You might want to consider going with LED grow lights and growing with a SCROG.
LEDs are finally powerfull enough to produce good results.
 

hoss12781

Well-Known Member
If you ask me a HID in that space is a fire hazard PERIOD. CFL or LED, or get a bigger space to grow in.
 

hoss12781

Well-Known Member
also growing in your dorm or student apartment is super risky man. Just wait till you move off campus. I know it's tempting but why fuck up your college career over growing a couple plants. Wait a year and get your own house or apt, you'll be neck deep in shit if you get busted in a dorm or student living complex and the ordor will be very difficult to mask. Seriously think long and hard about this.

Don't want to be a downer but if your student living arrangement is anything like what I had in college your living space is pretty much subject to search at any time.
 

MorroN

Well-Known Member
also growing in your dorm or student apartment is super risky man. Just wait till you move off campus. I know it's tempting but why fuck up your college career over growing a couple plants. Wait a year and get your own house or apt, you'll be neck deep in shit if you get busted in a dorm or student living complex and the ordor will be very difficult to mask. Seriously think long and hard about this.

Don't want to be a downer but if your student living arrangement is anything like what I had in college your living space is pretty much subject to search at any time.
I appreciate your warnings my friend, I will think long and hard before I start a new grow.
 

skunkd0c

Well-Known Member
hey morron, i had a 250w MH in a space a little bit bigger than yours for mother plants it worked ok, with a 4 inch inline extractor fan, although i would recommend a 6 inch or maybe a cool tube reflector as the temps would get into the upper 80s on hot days, that is ok for veg, but i wouldn't want those high temps in flowering

you said you were thinking of a 150w hps, if you look at the output of a 150w hps its pretty low like 14k lumen
200-250 watts of CFL will give the same amount of light / the better cfl bulbs will give more output than a 150w hps with much less heat, i have not used a 150w hps , i am sure they will still be pretty hot though compared to cfl

peace :)
 

chasta

Active Member
I would do some searches on stealthy's pc tower grow or some other PC grows . an old PC tower will fit almost anywhere. I too think it's a horrible idea though . Here in Oregon they have a 1000 ft cushion around schools . I believe it's a felony charge . Just do some investigation to make sure your safe .

I Have always looked at things from a "if i can't do the time , I ain't doing the crime"
 

zvuv

Active Member
A 150W mh would be very nice. I am currently using one in my veg cab. My experience was that the 150W MH way outperformed the 250W cfl setup I had previously and runs cooler.

It does not make sense to compare the lumen ratings of cfls vs HID. Lumens are a measure of light that is useful to human vision. Unfortunately the spectrum that humans use to see is mostly ignored by plants. So for growers Lumens are actually a measure of wasted output. Here is a more detailed explanation.
 
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