is it really needed?

im building a grow box that is:
veg =
1 1/2 ft by 2 ft

flower=
3 1/2 ft by 2 ft

(4ft high)
chambers are connected but seperated by a wooden wall that i will place there

at the top of box i am going to cut out holes to place the lights in so it will be outside the box really. at least the heat. i was wondering if i really needed an exhaust for this since it is so small. about 60 cfm or something. if possible can i just cut ventilation holes at the top and bottom and put a oscilating fan in the box? if its better to have an exhaust then thats fine ill get one i dont mind but what size would be good for intake? and not giving it power will make it passive right?

A smaller space with the same amount of light will require MORE ventilation, not less.
Regardless of the light fixture being outside the box, it WILL transfer heat through the light itself. If it's a closed grow, vent it.

proper ventilation is extremely necessary in a quality grow box, no matter the size...cutting vent holes on the top and bottom and putting n oscillating fan inside won't do much, you'll just be circulating the same stale air...and it's better to have an exhaust, check out newegg.com for some cheap yet powerful pc case fans, and with enough exhaust power, passive intake would do just fine...


SLB

smokeslikebob said:

proper ventilation is extremely necessary in a quality grow box, no matter the size...cutting vent holes on the top and bottom and putting n oscillating fan inside won't do much, you'll just be circulating the same stale air...and it's better to have an exhaust, check out newegg.com for some cheap yet powerful pc case fans, and with enough exhaust power, passive intake would do just fine...


Slb

Click to expand...

^^^^^^^^^^^^^^^^^ yes thats essential and correct.

sweet thanks i was looking at getting a small (squirrel cage?) exhaust and make some tubing that will be attached to the top corners of the box. sound good?

normajean123 said:

sweet thanks i was looking at getting a small (squirrel cage?) exhaust and make some tubing that will be attached to the top corners of the box. sound good?

Click to expand...

You need an extractor fan.

GROWFAQ.

Added by: MedMan Last edited by: MedMan.

Each fan has a rating that tells you how many cubic feet of air per minute (CFM) it will move. When dealing with above average temperatures you will want your fan to exchange the grow room air 3-5 times in one minute, so for a room that is 40 cubic feet, a fan that is capable of moving 120-200 cfm (cubic feet per minute) is recommended. If you only want to replace depleted levels of co2 and are growing in a closet using fluorescents, one room change per five minutes (divide room size by 5) will be adequate.

To calculate your room size, multiply Width by Length by Height, this will give you the CFM rating required for one room change per minute.

Air that’s exhausted will be replaced by fresh air, which is drawn from Passive Intakes-
located opposite the exhaust at the floor of your grow room (Recommended for closet grows) or forced in using another blower (recommended for larger grow rooms).

For internal circulation oscillating fans are In my opinion the most efficient devices for circulating air in a room. The gentle back and forth sway of the fan is very beneficial for the developing plants. These fans tend to keep anaerobic moulds down by constantly freshening any potentially stagnant air. Home improvement centres carry a large array of various types and styles of air-moving fans, there are wall-mounted styles available and most are relatively inexpensive.

NOTE: To convert CFM to CMH use the folowing formula CFM X 0.03 X 60 = CMH

k so of the these which would be best? (none that go over 150CFM cause it doesn't need to be that strong and dont want neg pressure)

http://www.ecogrow.com/index.cfm/product/642/mid/17/nid/0/home.html

http://www.ecogrow.com/index.cfm/product/303/mid/17/nid/0/home.html

http://www.ecogrow.com/index.cfm/product/2278/mid/17/nid/0/home.html

http://www.ecogrow.com/index.cfm/product/1963/mid/17/nid/0/home.html

normajean123 said:

k so of the these which would be best? (none that go over 150CFM cause it doesn't need to be that strong and dont want neg pressure)

http://www.ecogrow.com/index.cfm/product/642/mid/17/nid/0/home.html

http://www.ecogrow.com/index.cfm/product/303/mid/17/nid/0/home.html

http://www.ecogrow.com/index.cfm/product/2278/mid/17/nid/0/home.html

http://www.ecogrow.com/index.cfm/product/1963/mid/17/nid/0/home.html

Click to expand...

This one will be fine.............................


http://www.ecogrow.com/index.cfm/product/303/mid/17/nid/0/home.html

and a carbon filter can be put on it? and a backdraft damper?

normajean123 said:

and a carbon filter can be put on it? and a backdraft damper?

Click to expand...

There is no real need for a carbon filter just fix your ducting hose to both ends and thats all you need.
I dont know what a backdraft damper is ?????.
Carbon filters just restrict the fans suction and air flow.

sweet and this would be at the top correct?

normajean123 said:

sweet and this would be at the top correct?

Click to expand...

What the fan ????????????.
If so then yes mount it outside your grow space/room and have the ducting at the roof (where the hot air is) for maximum extraction.
This is my grow space and my fan is mounted in the roof around 2ft from where you see my extraction ducting.

thanks again.

so i got:

my lights
the fan you suggested for exhaust
2 mil mylar
seeds
moisture/ph meter
humidity dome with jiffy pellets

im going to be building my own grow box so really all im missing is the wood, duct hose, power tools, soil, pots, oscilating fans.
am i missing anything else that is needed to make a successful grow? mainly for the box.

normajean123 said:

thanks again.

so i got:

my lights
the fan you suggested for exhaust
2 mil mylar
seeds
moisture/ph meter
humidity dome with jiffy pellets

im going to be building my own grow box so really all im missing is the wood, duct hose, power tools, soil, pots, oscilating fans.
am i missing anything else that is needed to make a successful grow? mainly for the box.

Click to expand...

Join the friends list and message me as you need some more goods.

sweet but pretty much the main things for the room have been covered right?

lights and exhaust

since the rest is mainly directly for the plant. just wanna know cause im gonna start my grow next week. getting the last minute supplies for the box so i have it in time

normajean123 said:

sweet but pretty much the main things for the room have been covered right?

lights and exhaust

since the rest is mainly directly for the plant. just wanna know cause im gonna start my grow next week. getting the last minute supplies for the box so i have it in time

Click to expand...

There are many other things you need.

what are the things missing?
im also getting a surge protector from home deopot that has like 4 different slots that run on the timmer.

normajean123 said:

what are the things missing?
im also getting a surge protector from home deopot that has like 4 different slots that run on the timmer.

Click to expand...

Soil test kit/soil/perlite/veg nutes/water ph test kit/bug prevention/spare bulb and i think thats all for now unless i remember something else.

well the soil, perlite, veg nutes is what i was excluding since those i can get on the spot alot easier. whats the soil test kit for?
this is what i have for ph:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120568458874&ssPageName=STRK:MEWNX:IT#ht_1793wt_913

let me know if you think of anything else i might be missing