I just purchased a "CLOSETMAID 2-Door Stackable Organizer" it's dimensions are 31.5 inch high, 24.13 inch wide & 11.63 inch deep. I plan on only growing 1-2 plants. As far as input and output fans go I was planning on using 3 computer fans. 1 at the bottom right of the box for an input fan & 1 at the top left as an output fan. I was also planning and having a computer fan blowing on the top of the weed plant between where the lights and the weed plant are (to keep the light cool and keep the stems of the plant strong). Would this be adequate ventilation for a grow room of this size? Also, which size computer fans would work best for a setup this small?
sounds like a good idea to me..your dimensions are 24 inches long X 12inches wide X 32 inches height, your height isnt realative to the watts per sq foot ratio, only relative for figuring your appropriate CFM exhaust level. I would use 100-250 watts in that space Remember, you always want your exhaust fan to be stronger than your intake blower, this is so you get proper air turn over and your exhaust fan works better if it doesnt have as much competition from the intake. Personally, I use a passive intake air flow which I think is more effective for smaller areas and it saves money in the long run. You wont need a large duct fan for that small of a space, 100-125 mm would do the trick. Hope this helps you some MM
For that space, you don't need an intake fan - it will actually be counterproductive. Go with 2 passive intakes and an adequate exhaust fan and you will be in good shape. What kind of lighting are you going to use and do you plan to use a carbon filter? Both of those make a big difference in terms of CFM needs etc.
As far as lighting goes I'm going to use 3-4 40 watt 2700 colour temp. CFL's for the flowering stage & 3-4 40 watt 6500 colour temp CFL's for the vegetation stage. I am going to be growing one plant using the LST method. Could you guys elaborate on what you are saying I don't know much about intake/outtake and ventilating so any explanation/elaboration would be helpful? I was thinking of using an intake fan at the bottom left and an out take fan at the top right, this way fresh cold air comes in the bottom and as the hot air rises its goes out the top. Then one fan blowing on the top of the plant area as well as the bottom of the lights (same fan wud be blowing on both top of the plant/lights), that way the lights stay cool and the plant gets stronger. I was planning on using computer fans for both intake, outtake & for the plant/lights. Why wouldn't I need an intake fan? and what do you mean by 2 passive intakes what would be an example of a passive intake fan? and an adequate exhaust? Would I need a carbon filter for a 1 plant grow of this size?
LST is a good plan given the CFL lighting and size of the space. What you want to do on the intakes is cut/drill two 2" holes at the bottom of your cabinet and then use some 2" pvc 90 degree fittings to create an S shape that will serve as your light traps. You will fit these into each of your two intake holes. This will allow air to enter your cabinet but the s shaped pipe will not let light in or out. The reason you don't need an intake fan is that an adequately sized exhause fan will create more than enough negative pressure in your cabinet to constantly pull fresh air in through your 2 passive intakes and exhaust it out through the top of the cabinet. You want your exhaust fan up towards the top of the cabinet pulling air into the cabinet and exhausing it out. The key is to get a fan that will exchange all the air in the cabinet at least every 5 minutes. You can find some posts using search in here that tell you how to calculate your required exhaust fan CFM. Keep in mind if you are going to run a carbon filter, you generally need to almost double that CFM need. For example if the calculation says you need a 70 CFM fan, you probably want one more in the range of 100-120 CFM to account for the air resistance created by the carbon filter. An intake fan in this situation in addition to an exhaust fan would likely prevent the negative pressure you are trying to achieve inside the cabinet by pulling too much air in too quickly.
Okay thanks for the advice do you think a 230mm fan will do the job for outtake? also, will one intake hole suffice or should I plan on using 2? Also, as far as positioning goes, I know I want the outtake at the top of the box and the intake at the bottom but are their any specific locations aside from intake at the bottom and outtake at the top that I should take into account? (i.e. more specific locations top-right-hand corner, or top-center?)
You got your locations right, I exhausted at the point that the plants would be at maximum height. Intake as low as possible. For those 3 - 120mm fans I have a 120mm high and 360 mm wide Intake.
Are you going to run a carbon filter? If not that fan should work well and I would do two intakes but one would likely be enough. If you go with a filter, you need a much stronger 4" fan. As far as location I would ensure the exhaust outlet is on top or on the opposite side of the intakes towards the top of the cabinet. The goal is to maximize fresh airflow in the space so the farther apart they are the better and you want intakes on the bottom to pull cool fresh air in. Exhaust on the top b/c hot air will always rise and that's what you want to expel out of the cab.
I won't be running a carbon filter, so tell me if this makes sense, top left of the box will be a 230mm fan for outtake, bottom right of the box 2 holes 2'' each with the S shaped thing you were talking about to prevent light lose/light coming in, will these inputs & outputs be sufficient for this grow space? Also, should the intake holes be beside each other? I know they should be on the bottom right because the outtake is on the top left. But is there any specific location like beside each other, etc. that I should take into account?
perfect thanks for the help, do you know of any auto-flowering strains that help with both pain and anxiety? Or two autoflower strains 1 for pain and 1 for anxiety?
I picked up the seeds today Feminized Autoflowering BigBang & Feminized Autoflowering 60 Day Wonder, I bought a 230mm output computer fan I still need to get the adopter (I also have a 140mm & 120mm computer fan as well). Which type of adapter would work best for this? I'm looking to be able to plug it into an outlet. I also picked up a bunch of ABS 1.25 inch 90 degree elbows put together they create a S shape, the diameter of the S shaped device is 2 inches so it'll fit perfectly in the 2 inch passive-intake holes. just like EZ was talking about. Do you think these S shaped devices that I will add to the passive intake holes will do the trick at keeping air flow coming into the grow box without allowing outside light to come into the box or light from leaving the grow room? I was also debating attaching a similar contraption to the exhaust fan area, that way light would not leak from the box and outside light would not be able to get into the box through the exhaust fan hole. Does that make sense to do? Are there any other ways to make it so that light doesn't go from &/or into the grow box through the exhaust hole where the exhaust fan is? I also got "White Kitchen & Bath SILICONE" I was planning on using this along the inside edges of the entire grow box that way it will stay more air tight. Does that make sense and is worth my time lining the inside of the box with "WHITE Kitchen & Bath SILICONE"? Pro's & Con's of doing this? Also, I keep looking for formula's which can tell me how to calculate which size exhaust fan I'll need to get fresh air every 5 minutes in my box, every formula I try gives me very strange CFM numbers. All the threads I've looked at use this formula: l x w x h = cf / m = cfm m = air exchange in mins So for my grow: 2 (feet) x 1 (feet) x 2.5 (feet) = 5 Then... 5/5 (minutes) = 1 cfm Can anyone tell me what I am doing wrong with my calculations? Why my CFM readings are so far off? Which size computer fan can I expect to use as the exhaust fan in my grow box? What CFM reading should the fan I'm using as an exhaust have?