Newbie looking for ventilation Tips!

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Mar 31, 2011
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Hi all

I am new to the forum and this is my first post , i have just set up a grow tent 80x80x160 and i wondered what the best extraction fan is for stealth ??

Should i put carbon filter inside or outside the tent ??

Will be using cfl 250watt , 1 for veg and 1 for flowering ....

Any help is greatly appreciated ...

Peace all

you want it to go carbon filter - light - fan - outside or carbon filter - fan - outside if you dont have an air cooled hood.

Use insulated ducting on each end of fan to reduce noise. Could make a box for the fan as well which would reduce sound.

take care and be safe

Ty Jericho, would a 4 '' fan be decent enough for my tent size or should i go bigger?? , I have had tent on for 2 days now without extractor as i dont have one yet obv, humidity is averaging at 79%, i wondered if this is a workable climate for my plants to grow?, only got strawberries in there at the moment while i'm testing the tent , going to connect extractor fan to top vent , 3 other vents at bottom and middle for inlet co2 , how many vents should i leave open ?? should i connect a fan to pull air in also or is this over doing it ??

Ty for any info at all...

Peace all
If you look at my GJ in my sig there are pics of my tent set up on the 1st page.

Fan speed depends if you are going to control humidity and temp from light with fan as well.

My fan exchanges the air 3 times a minute in my tent. its 1m x 1m x 2m and i run a 600w in there and my temps are about 10 degrees higher than they are outside, humidity at about 50%.
Im using a cfl reflector canopy with a 250watt bulb , i have a blue spectrum bulb and an orange , heat does not seem to be a problem although further testing is needed , ill check out that page ty Sir that is most helpful and appreciated. i have a hps 200watt with reflector there also but will prob be 2 worried to use when it comes to the time as i keep hearing horror stories about diff in power usage but again this is something i plan on researching more ...

Peace all
Lots of info to take in throughout your threads by the looks of it Jericho .

Ty Buddy.....:)

Peace all
Welcome brother to the oracle of home grow. I don't know how much yu know about growing canabis but there is a lot to know so if yu dont, Yu got a lot of readin to do b4 yu put a bean in the soil (if yu choose to use soil). I have to tell yu now from my experience, unless yer gonna grow 1-2 plants at most, yer lighting is too weak and will cause the plants to stretch. CFLs are ok for germinating or if yu are using 6-8 in that size room. the most for yer money is gonna be 1 400w Metal Halide, AND 1 600w High Pressure Sodium (both in either reflector hoods or cool tubes. check out 'the Hemp Goddess's" cool tube DIY on here). These will be the best for the money spent in operation and in yeild potential and all around health of yer grow. As far as ventilation? 4" or 6" is determined by the size of yer tent openings, but on fans look for the CFM capacity of fan and reccommendation for tent (don't want to create a cyclone or collapse the tent haha). There are some really nice inline fans that r very quiet and affordable. I wouldn't worry too much about filtration unless yu know that yer strain of plant is a "dank weed". I buy from "" online for practically all of my stuff for my grow as they are real good and very good prices. Yu have certainly come to the right place for knowledge as these nice people have amassed a lot of experience in multiple methods that r solid yeild producers. Don't be afraid to ask even the seemingly dumbest questions. I have learned a lot and am still learning, and I would be happy to answer anything I can as I have developed a passion for growing this beautiful weed.
I don't know about strawberries, but I found in my grow-lab that the vegging plants like humidity between 45%-65%RH. above that (except for clones and seedlings) and they start to stress and not drink their water as they can't sweat as good, and regulate inner heat as good as in lower Relative humidity. for the youngins, I use a humidome to maintain higher RH.

Ty so much for your input Hushpuppy , what a superb welcome into this wonderful community i dont know why i have not searched for a good forum sooner as i have been Hitting my bong for best part of ten years now...:),i suppose the reason for joining is because i want to try growing my own due to terrible dealers and crap weed in general, i am 36 and want to get away from going to crappy dealers and just self sustain ...:), i am actually if i get the balls to go ahead with it planning to only grow 1 or 2 as i smoke a little amount and 1-2 oz would generally be plenty for a few months and i could start a cycle. Could i get away with growing that amount under the cfl's buddy??. Done a fair bit of reading on lumens and stuff and i kind of understand what it all means but still need to do more reading up .Think i'm going to go with a 4'' inline extractor and carbon filter , I would really like to hang that inside and think there will probably be room inside the tent. I really just have a lot of worries about doing it in general , i have told nobody and plan on keeping it that way i also plan on not taking pics or video . i know that sounds terrible but it's just the way i feel at the moment . May change with time ....;-)

Ty HushPuppy Most Appreciated
I know what yu mean about security...good mindset to keep. As far as CFLs there may be others who disagree with me but I like the T5HO systems. They put out more lumens per watt than the CFL bulbs and are low heat producers. Yu can go online and buy single 2' 3' or 4' individual bulb fixtures, or any one or more of the multibulb fixtures, both for pretty decent prices. I buy a lot of my stuff from 'discount hydro' and 'access discounts'. they have good prices, quality and shipping, and right now everyone is buying gardening stuff for spring so yu don't have to worry about big brother monitoring these web sites activities. I buy the individual "sunblaster" 3' for $24ea. and have 6 of them in my grow room for veg and a 600w HPS for flower, but yu could probably get away with the T5, 3500K for flower and the 6500K for veg. I try to achieve over 25000 lumens for a 3'6"x3'6" room for veg then turn on the HPS with the T5 when in flower. Lumens are critical for healthy growth. Yu 'almost' can't have too much during flower as long as yu can control heat buildup. I know also that yu don't want to invest a lot of money in equip starting out. Yu may be ok with the lights yu have if yu incorporate the HPS that yu have, about 4-5wks after germ. Don't worry too much about electricity cost, if you run 500w total in lighting that is equivalent to a 5 room house with 100w lightbulbs in each room. I have been running roughly 800w of lighting, fans, pumps, AC and sometimes heat, and my bill hasn't changed more than $30 so far. I think yu should be able to work with just 2 plants at a time without any problem, and as yu get good at optimizing yer setup, yu will improve yer yeild from a given strain by cloning and using SOG or SCrog methods. Keep us posted, yu will find it addictive, I do.
yeah i will be making daily posts if i begin a grow and i'm already finding it quite addicitive just reading up on it all hehe, i think i could get away with useing my cfls for vegging then switch to my hps for flowering , might try auto's first i'm not really sure , got some all mix bio-mix and half mix bio-mix for seedlings. Not too worried about electricity cost now after looking into it ,Should i just leave one vent untied for inlet air or should i leave 2 untied ,lol i'm such a noob ....

Thanks for reply HushPuppy
Yu will find a lot of things yu do with yer grow will vary in what is best for that situation. given the size of yer tent and lack of heat issue, "I" would leave just one vent open for now and even put some kind of fine screen mesh over it to keep out dust and critters. with that, look at it and see if it is pulling to hard on the one opening, causing too much wind on the plants or pulling weirdly on the tent (yu never know how things will do until yu see them in action) if either happens then open the second vent to balance out the air draw. Make sure yu get a thermometer/hygrometer guage to keep in the tent to monitor the weather in there. Walmart has a good digital meter that runs on a "AA" battery. I try to maintain 45-65% humidity and 73-80degree temps. if yer grow is in the house, yu will supply it with a nice amount of CO2. I am experimenting with CO2 injection right now to see if it is worth the cost/effort. there r a lot of interesting ways to produce it without one of the more expensive methods used commercially. Don't feel bad about being a noob, I have been working my grow for 9 months and have done enough readin to make my eyes bleed, and I still feel like a noob every time I read something on here that I hadn't thought of b4. Yu wanna really get yer socks blown off? go pick up the latest copy of HighTimes magazine n "HTs greatest growrooms 2011" You'll choke on yer own drool!!
None of the homemade CO2 systems are worth anything--save your money, time and energy. And there is far more to CO2 enhancement than simply putting more CO2 into your space--you need an air tight space, you need an air cooled light, you need lots more light, you need higher temps, etc, etc.

If you want to improve your grow, I recommend getting more/better light and getting your ventilation set up. A space that is 80 x 80 is about 7 sq ft and needs 35000 lumens for flowering. The larger CFLs run about 50 lumens per watt, so a 300W CFL may only be giving you 15000 lumens--far short of what you need. Contrast this with a 400W HPS which will put out between 45,000 and 55,000 lumens depending on your bulb. If you are concerned about electricity useage, an HPS is the only way to go. Lumen for lumen, CFLs cost more to purchase initially, put out more heat, cost about twice as much in electricity every single month and produce substantially less bud.

I wouldn't worry about getting a carbon filter unless you find you need it--I do not run a filter. You will need at least a decent 4" centrifuge fan for exhaust and an oscillating fan to more the air around. You may find that you need more.
Welcome to MP.....I wldnt waste my time, energy and money on DIY CO2....
Thanks hemp goddes thats great input has really helped, my fan came today so i set up to extract from the top of tent , i have 2 oscillating fans inside , now got a 400w hps bulb for my ballast and will be using during flowering and sticking to cfl,s for veg period, i do need the area to be sealed better , the door to my basement is round the back of my house and its not that great i need it to be more airtight than it is to lower the humidity a little, will post back min and max temps after a week with fan and other bulbs running...

Thx Again..


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