Ventilation

Shastafarian

Well-Known Member
MEOWWWWWWW!!!! Now u guys its about teaching and being humble No need to bost or brag. Lets show some Respect & Love no matter what the other guy says. We are all in it to win it. SO Keep your head in the game and think logically about your grow problems at hand. The answers could be right under your nose. You just need to take a deep breath inn and smell that sweet aroma of success for a second. Go green organic and get the best green then you will be successful 100% and healthier. Keep the AC on if u want, it will grow still but u get some airy wispy bud due to the plant trying to cool itself if your temps are high. keep the AC on even in a window seal or in front of the sliding glass door/ window. It will be a happier plant at 78-83F ambient room temp and will bless you with tighter crystal coated trichomes of pure dankness if you have a good phenotype already figured out. But ya man the calyxes will be a little more swollen and thus adding weight to your harvest. So you be the judge and start making some good decisions. We can't be there with you and see how its reacting but thats what made us pros. We take the best info and applying it or modify it to improve the advice and then return the favs to the next dude thats in need. But not to make him feel inferior or like he is a bone head. LOVE LOVE LOVE My friends
 
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Shastafarian

Well-Known Member
Thank you Kind Sir , yes I feel you will need the 8" set up centrifugal fan and 8" duct tubing. I don't see a real need for the insulated tube but it will help a little if AC is being channeled through. If you want you can do what brimck325 said, it works okeedillydoky especially if you already purchased that size fan and filter this is a good idea. If not than look for a 8" set up and you will get the best results of air cooling and filtration efficiency. If you reduce it to 6" it will reduce the efficiency of the air flow. It works if its just a air cooled hood/ light and no filter than I see his idea being plenty good enough.
 
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Redvirgo

Active Member
Ok, so back to the problem with ventilation. From every page that I have read and every member who has shared expert advice, in order for a passive air intake system to properly work without creating too much negative airflow the intake hole/s must be 3 times the size of the exhaust. Meaning that if you are using an 8" inline fan to exhaust then you should be pulling in air through a 24" opening. The disadvantages to a negative airflow room is that it attracts dust much faster with the increase in negative pressure. A positive air flow environment is almost dust less and is what is used in most big computer rooms and labs to combat this problem. To create a positive air flow environment you would need to have a fan on the intake pulling in more air than exhausting out and one on the exhaust both with speed controllers to control just how much pressure you wish to recreate in your grow area.
I ran into this same problem when setting up my grow tent in my closet in my bedroom after renovations. The problem that I ran into after getting everything set up and ready to grow was the intake air that I needed to pull into my tent through the wall in the closet that I built and wired. I have a 2'×4'×7' gorilla tent, 4"×12" phresh carbon filter/ ducting/ 4" hurricane inline fan/ ducting through the roof and up through the closet roof into the bedroom. Running kind led lighting equivalent to a 600w hps but half the electricity and virtually no heat. I am putting in a new 10"×10" air return register (needed to go with 12"×12" according to specs for a 4" exhaust) with filter in the side of the closet and running 8" insulated ducting from there into the closet and then into the grow tent. This was the best possibility for me, the most cost efficient, and the stealthiest since I didn't need to get another fan.
 
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Shastafarian

Well-Known Member
Awesome man I have almost the exact same set up that I just got started setting up. Im getting another tent coming in a couple days for 12/12 its a Ipower 48"L x32"w x60"h Tent with a 6" Phresh 400cft Carbon filter a 435cfm Hurricane inline fan and a 600w Digital dimmable HPS with 6" Air Cooled sealed hood. I then got a small clip on oscillating fan and a 6" black insulated duct tubing for my Hurricane Centrifugal fan, its better than the reg cheaper duct for quietness and temp control. Then I got the 48"x24"x48" LightHouse Hydro Tent not recommended but its ok for veg which is what I got it for. With a 4ft 6tube T5 system in it and a small oscillating fan circulating CO2. I put the Exhale mushroom bag for a natural boost of CO2 to my veg tent which last 3-4months and sealed the tent other than one intake hole for AC from my portable rolling unit to help battle the 95-97 degrees I was dealing with. I wish the T5 didn't put off this much heat but I think it may be due to a cheaper Enviro Grow system I purchased. I then got all the Biobizz full Line along with Hygrozyme, SuperThrive and some Sweet berry. Bought this 2litre Co2 bottle from TNB that produces over 950ppm for 2- 3wks strong for the budding stage and tent. I will be running the Phresh filter in my bedroom through my bloom tent and cooling the 600w bulb with negative air pressure from my AC shooting the exhaust air outside my2nd story window. The Tent should be cooled pretty good Im hoping with this fan but I will have it on a controller turned down a bit. I need stealthiness and low electric costs because my electric is figured in with my rent. I have grown like this before and I think the electric should only jump the bill 30-40$ at most and since I just turned it on with the change of seasons to spring I think It won't be as noticeable with the natural bill increasing this time of year.
 
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Redvirgo

Active Member
Awesome man I have almost the exact same set up that I just got started setting up. Im getting another tent coming in a couple days for 12/12 its a Ipower 48"L x32"w x60"h Tent with a 6" Phresh 400cft Carbon filter a 435cfm Hurricane inline fan and a 600w Digital dimmable HPS with 6" Air Cooled sealed hood. I then got a small clip on oscillating fan and a 6" black insulated duct tubing for my Hurricane Centrifugal fan, its better than the reg cheaper duct for quietness and temp control. Then I got the 48"x24"x48" LightHouse Hydro Tent not recommended but its ok for veg which is what I got it for. With a 4ft 6tube T5 system in it and a small oscillating fan circulating CO2. I put the Exhale mushroom bag for a natural boost of CO2 to my veg tent which last 3-4months and sealed the tent other than one intake hole for AC from my portable rolling unit to help battle the 95-97 degrees I was dealing with. I wish the T5 didn't put off this much heat but I think it may be due to a cheaper Enviro Grow system I purchased. I then got all the Biobizz full Line along with Hygrozyme, SuperThrive and some Sweet berry. Bought this 2litre Co2 bottle from TNB that produces over 950ppm for 2- 3wks strong for the budding stage and tent. I will be running the Phresh filter in my bedroom through my bloom tent and cooling the 600w bulb with negative air pressure from my AC shooting the exhaust air outside my2nd story window. The Tent should be cooled pretty good Im hoping with this fan but I will have it on a controller turned down a bit. I need stealthiness and low electric costs because my electric is figured in with my rent. I have grown like this before and I think the electric should only jump the bill 30-40$ at most and since I just turned it on with the change of seasons to spring I think It won't be as noticeable with the natural bill increasing this time of year.
That's an awesome setup you have going there. I wish I currently had the room for a veg tent as well. I have my controller turned down to low at the moment and set on a timer to run 15 minutes every hour and a half, can barely hear the air moving outside of the tent and closet.
 

Shastafarian

Well-Known Member
Turns out I can't run my veg and bloom tent in tandem or it pops my 20amp fuse. I can't figure out what to do other than call an electrician to change it to a bigger 30amp? if you have any ideas that would be nice to hear? thanks
 

mr sunshine

Well-Known Member
Turns out I can't run my veg and bloom tent in tandem or it pops my 20amp fuse. I can't figure out what to do other than call an electrician to change it to a bigger 30amp? if you have any ideas that would be nice to hear? thanks
What kind of light are you vegging with?
 

Shastafarian

Well-Known Member
I have a T5 Enviro Grow 6 bulb 4ft inside a small 48"Tall x 24"wide x48"Length veg tent. I have to keep it closed because I am using the mushroom bag for some C02 better results but I get 98F unless I open one top 6" hole to allow my portable AC I put it right up to that hole with card board duct I made to channel real nice inside to a fan on the inside that circulates that air for a better 80-83F. I think I need the 88- 90F to really see the CO2 blast off. Anyways not to get off topic but with my AC which I will have to run because it just is plain hot as balls in my room that I have to live in also. I rent a 1 bedroom and share a bath. I have to be super stealthy and chill but I got the Phresh 16" 400cf filter with a Hurricane 435cfm 6" to cool a 600hps. I have some auto strains to zip through that should be easy and chill Cherry Bomb auto and Wappa auto they kinda suck i know now but Im gonna run em anyways to get something. then I got White Widow x Hindu Afghani kush 3pkfem should get 1 mother from and I got HashBar OG which is supposed to be a chill less stinky cross of OG because it was a female HP from PNW that was bred for discreet stealthy growers with nosey neighbors. Gonna put the filter in my bedroom I guess with the air blowing through my 600w hps sealed air-cooled dimmed down 75% should be roughly 450w hps but should do 8 plants 2gal pots soil in another 48"x36"x48" tent. I already pop my 20Amp fuse now with the 6 bulbs running and everything else I can possibly turn on in the room to try and simulate and with my portable 8a AC it trips it everyonce in a while.But if I turn the 600 and fan on I will keep popping it. I am right next to the fuse box so I easily trip the breaker back over but I don't think its good to do alot. I don't think an electrician is gonna be cheap. I wonder If I could manage a DIY it with the right tools and youtube video. Or if you have other better Ideas Im all ears? Thanks
 

Redvirgo

Active Member
I have a T5 Enviro Grow 6 bulb 4ft inside a small 48"Tall x 24"wide x48"Length veg tent. I have to keep it closed because I am using the mushroom bag for some C02 better results but I get 98F unless I open one top 6" hole to allow my portable AC I put it right up to that hole with card board duct I made to channel real nice inside to a fan on the inside that circulates that air for a better 80-83F. I think I need the 88- 90F to really see the CO2 blast off. Anyways not to get off topic but with my AC which I will have to run because it just is plain hot as balls in my room that I have to live in also. I rent a 1 bedroom and share a bath. I have to be super stealthy and chill but I got the Phresh 16" 400cf filter with a Hurricane 435cfm 6" to cool a 600hps. I have some auto strains to zip through that should be easy and chill Cherry Bomb auto and Wappa auto they kinda suck i know now but Im gonna run em anyways to get something. then I got White Widow x Hindu Afghani kush 3pkfem should get 1 mother from and I got HashBar OG which is supposed to be a chill less stinky cross of OG because it was a female HP from PNW that was bred for discreet stealthy growers with nosey neighbors. Gonna put the filter in my bedroom I guess with the air blowing through my 600w hps sealed air-cooled dimmed down 75% should be roughly 450w hps but should do 8 plants 2gal pots soil in another 48"x36"x48" tent. I already pop my 20Amp fuse now with the 6 bulbs running and everything else I can possibly turn on in the room to try and simulate and with my portable 8a AC it trips it everyonce in a while.But if I turn the 600 and fan on I will keep popping it. I am right next to the fuse box so I easily trip the breaker back over but I don't think its good to do alot. I don't think an electrician is gonna be cheap. I wonder If I could manage a DIY it with the right tools and youtube video. Or if you have other better Ideas Im all ears? Thanks
If you have the fuse panel close and an extra (blank) fuse slot in there, then it is pretty easy to drill a hole through the wall or floor and run some 3 wire electric wire directly from inside of your room out to the fuse box. The most hazardous part of doing this yourself is connecting the new breaker to the new wires and installing the breaker in the box (if you don't have experience around live wires and electricity). After running the wires you can then install an electrical outlet and box wherever you want in your room. You can then have an electrician come out and install the breaker if you are not comfortable doing it yourself. I ran all new wires from my room under the house (crawl space) and right up to the breaker box, then had a friend with experience connect the new breaker into the fuse box. I have 3 separate outlets branched off of 1 15amp fuse and 12/2 wire which has white/black/ground wire. Powering my whole closet bubbleponics system, inline exhaust fan, circulation fan, LED lights, a 32" flat screen tv, and charging cell phones with no problems. The difference in the electrical load that you are pulling from your room is much more. Your 2 biggest electrical culprits are that AC unit and your lights. If that is not possible then the other option is to run a good size gauge but short as possible extention cord from another outlet in the house on a different fuse into your room where you need it.
 
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Shastafarian

Well-Known Member
Thanks bro thats some good feed back. I don't know if I can do that electric work but I may have to wait for now and hold off on popping seeds.
 

Redvirgo

Active Member
Patience is gonna be good for my success.
It most absolutely will be. I have had a great deal of patience over the last year that it took me to get my grow area complete and ready to grow. Everything has gone better than I had envisioned and planned for, all the extra waiting and down time I have used to gain more and more knowledge and patience.
 

COCO0419

Member
I am a newbie and ive been doing so much research and im pretty much irritated....Just cant seem to make any sense of the exhaust and vent situation... I have a 4x4x6.5 grow tent, so first of all I was wondering is it necessary for me to put my carbon filter in the tent when there will be no odor during the first 3 or 4 weeks? I have a 6" air cooled hood with 600 mh and hps bulbs....would I be able to just attach the fan which is a 6" inline fan to my hood now am I suppose to put ducting on the other end of the hood and run it out the tent and I would want to run it out the window?? but what about my fresh air intake, my tent is in a 8x10 room which has a window and the door will be shut so if I was to leave the window open could I just open the bottom vents will that be enough airflow or will I need another fan at the bottom of my tent...IM SO CONFUSED AND IRRITATED-CAN SOMEBODY PLEASE HELP ME UNDERSTAND ALL OF THIS!!!!!
 

JSB99

Well-Known Member
I am a newbie and ive been doing so much research and im pretty much irritated....Just cant seem to make any sense of the exhaust and vent situation... I have a 4x4x6.5 grow tent, so first of all I was wondering is it necessary for me to put my carbon filter in the tent when there will be no odor during the first 3 or 4 weeks? I have a 6" air cooled hood with 600 mh and hps bulbs....would I be able to just attach the fan which is a 6" inline fan to my hood now am I suppose to put ducting on the other end of the hood and run it out the tent and I would want to run it out the window?? but what about my fresh air intake, my tent is in a 8x10 room which has a window and the door will be shut so if I was to leave the window open could I just open the bottom vents will that be enough airflow or will I need another fan at the bottom of my tent...IM SO CONFUSED AND IRRITATED-CAN SOMEBODY PLEASE HELP ME UNDERSTAND ALL OF THIS!!!!!
Here are a few reasons I can think of why you'd want the filter on all the time:
  • keeps the air in the area cleaner (in the room if exhausting there)
  • keeps dust out of your ducting and hood
  • Having to lean over plants to hook up your filter when it's time can be difficult and you run the risk of dropping it on some poor unsuspecting plant
I don't think you'd want to attach the fan to the hood. I've seen it done, but I would think it would make one side unusually heavy. Also, unless you have a really small hood, you might not have the inline room, especially when you take into account the exhaust hooked up to the fan.

Here's the normal flow of air:
  1. Ambient room temp of the air in the room the tent resides in is drawn into tent by negative pressure from fan
  2. tent air is drawn into the filter, and this is why you want air coming in at the lowest point in the tent, so it travels through the plants to the top
  3. The scrubber is connected to the hood via ducting
  4. The hood is connected to the top-most tent port via ducting
  5. The fan is connected to the to exhaust port via ducting to suck the warm/smelly air out of the tent
Whether or not you want to vent the warm air outside is up to you. Here's how I'll be setting up my new grow:

Same size tent as your's in my 10x16 insulated shop with 1k mh/hps hid lights
During the winter I will exhaust the air from the tent directly into the shop to warm the air
When the light is off and not producing heat, I will use a space heater to regulate the temps so it doesn't get too cold.
I will have a thermostat controlled air intake fan and vent for when the light makes the shop too warm. The outside air will cool down the shop and will close when the room is where it should be.

In the summer, I will run a window a/c in my shop to keep the room cool.
I will exhaust the air outside the shop.
I will use insulated ducting post-fan to prevent additional heat from being put back into the room.

There are other setups that are variations of this.

This is a pretty typical setup, except that it's recommended putting the fan outside of the tent so you don't add any heat:



Hope that helps
 
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JSB99

Well-Known Member
but what about my fresh air intake, my tent is in a 8x10 room which has a window and the door will be shut so if I was to leave the window open could I just open the bottom vents will that be enough airflow or will I need another fan at the bottom of my tent
Leaving the window open can potentially allow intruders, so be careful. You can run a portable a/c in the room. Then you would exhaust the air from the tent AND the ducting from the portable a/c outside.



IM SO CONFUSED AND IRRITATED-CAN SOMEBODY PLEASE HELP ME UNDERSTAND ALL OF THIS!!!!!
This is supposed to be fun. Do your research here. You will learn everything you need to know. Take a deep breath and relax bongsmilie
 

COCO0419

Member
JSB99 thanks for responding; Now you said you were exhausting the air out your grow tent into your shop, so where is your fresh air coming from? Like do you have another fan, do you just have the vents at the bottom of tent open or what? Ive been doing A LOT of research and if I would of known that growing my own medical marijuana was going to entail ALL OF THIS don't think I would've started, I am TOO FAR IN NOW-financially and time spent researching to change my mind. I must admit Im starting to get scared that I may fail cause there seems to be SOOOOO MANY THINGS that could mess up your grow (ph problems, nutrient lock out, over feeding, pest control, heating problems, not enough fresh air intake, co2 like I can go on & on) and with the money Ive spent- I cant afford to mess this up. This is really frustrating and irritating me cause you go online for help and 1 person says its better to suck the heat thru the lights then somebody else will say its better to push the heat,thats just 1 example like at the end of it all im left still confused and not knowing what to do...which is why Im frustrated...this is going to be long but I need somebody to vent to (lol)! So you say to put the carbon filter in the tent from the beginning to the end...well I was under the impression that the filter was used for odor and there usually no odor till the flowering stage. Far as putting the carbon filter in I was more like wanting to keep it outside the tent due to overcrowding the tent. So does it HAVE TO BE IN THE TENT? or will it only work if its inside the tent? Don't know where youre from but I am in Pennsylvania and the weather is cold right now that's why I considered just opening the window to get fresh air into the room and just open vents or possibly putting a fan by the window, the room its in is on the second floor so I don't have to worry about intruders (lol) ok im gonna stop here although I do have more questions I will wait for my response on this...then come at you with some more questions. your response will be greatly appreciated
 
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