Ay need for a intake fan?
- Thread starter rick19011
- Start date
Slipon
Well-Known Member
your cool, no need, just have one/a few passive intake hole`s down low (normally 2-3x the size of the out take depending on how strong your ventilation is) physics take care of the rest, as air is "pulled" out of the tent it have to be replaced with sum thing, after all we are still on earth 
so it will sug in fresh air automatically, keep the intake low as cool air drops and out take up high as hot air travels up
I used a few meters of left over ducting from my 600W HPS/cool hood (when I used one) to make 3 tubes as intake, both to light proof em (a few bends) and so I could direct the fresh air coming in to where I wanter it, right beside my plants down lower so it pass em on the way up to my filter/outtake
best of luck
EDIT: btw you want a bit of under pressure/negative pressure in there (need to see the tent getting pulled in a inch or so when you close it) so you know all odor is going out through your filter and now we are talking about filters, they are great but they do get "used up" so as I see it there is no need to add them before the plants begin to stink/flower, they roughly last a year, you could make that two if you only run em half the growth`s
also high humidity is not the best for the active carbon so try not to get it to high, plants also want a RH on around 40-50% so no need to have +70% at any time
so it will sug in fresh air automatically, keep the intake low as cool air drops and out take up high as hot air travels up I used a few meters of left over ducting from my 600W HPS/cool hood (when I used one) to make 3 tubes as intake, both to light proof em (a few bends) and so I could direct the fresh air coming in to where I wanter it, right beside my plants down lower so it pass em on the way up to my filter/outtake
best of luck
EDIT: btw you want a bit of under pressure/negative pressure in there (need to see the tent getting pulled in a inch or so when you close it) so you know all odor is going out through your filter and now we are talking about filters, they are great but they do get "used up" so as I see it there is no need to add them before the plants begin to stink/flower, they roughly last a year, you could make that two if you only run em half the growth`s
also high humidity is not the best for the active carbon so try not to get it to high, plants also want a RH on around 40-50% so no need to have +70% at any timecontraptionated
New Member
Excellent answer from the guy before me. An intake fan is a great way defeating the concept of negative pressure which is necessary for odor elimination and stealth . I think Jorge mentions the use of an intake fan in his grow bible but he is wrong.