How many do I have open? At first I only had one open but the air only being drawn from there seems to be causing the closest plants to get windburn/curling. I tried to open them all but to even get some negative pressure I have to have the fan running really high. I don't mind but the fan is oversized for the tent so I'm struggling with balancing negative pressure/wind speed etc.
I've settled on two for now but still not sure if it's right?
Any advice would be much appreciated.
Welcome to the cannabis school for new growers section. In this section you can ask and get answers to questions about growing cannabis. Whether you are are new to growing cannabis or thinking about getting into the hobby, there are no silly questions so ask away. To become part of our online cannabis growing community click here to register.
Passive air intake flaps
- 2-Scoops
- Registered User
- Posts: 6237
- Joined: Mon Nov 26, 2018 2:10 pm
- Location: Not far away but far enough
- Has thanked: 3645 times
- Been thanked: 3521 times
- Status: Offline
Re: Passive air intake flaps
1 or 2 should be fine, i run a passive inlet myself in my grow cupboard. I've always gone by x1.5 to x2 times size passive inlet hole to your extraction fan, but i see your running oversized gear. But yes i would think 2 is more than enough in a smallish grow tent.
"But your still looking at me that same damn way............ Like i just shit in your scrambled eggs" > Negan, Walking Dead
-
- Registered User
- Posts: 31
- Joined: Tue Sep 21, 2021 7:24 pm
- Has thanked: 1 time
- Been thanked: 21 times
- Status: Offline
Re: Passive air intake flaps
What size tent and what CFM is your fan?
- These users thanked the author E.p_grower for the post:
- Growmie (Wed Oct 06, 2021 10:38 pm)
- Growmie
- Registered User
- Posts: 908
- Joined: Sat Sep 18, 2021 10:38 pm
- Has thanked: 519 times
- Been thanked: 586 times
- Status: Offline
- Growmie
- Registered User
- Posts: 908
- Joined: Sat Sep 18, 2021 10:38 pm
- Has thanked: 519 times
- Been thanked: 586 times
- Status: Offline
Re: Passive air intake flaps
Thanks mate, two open seems better than one at the moment as one on its own causes too much of a kind of wind vortex and was stressing the smaller plants. With two though it seems fairly stable. Thanks mate!2-Scoops wrote: ↑Wed Oct 06, 2021 1:16 pm1 or 2 should be fine, i run a passive inlet myself in my grow cupboard. I've always gone by x1.5 to x2 times size passive inlet hole to your extraction fan, but i see your running oversized gear. But yes i would think 2 is more than enough in a smallish grow tent.
- Anonymiss
- Registered User
- Posts: 6
- Joined: Sun Oct 03, 2021 11:20 am
- Has thanked: 8 times
- Been thanked: 36 times
- Status: Offline
Re: Passive air intake flaps
Negative pressure isn't all it's cracked up to be - it makes no difference to the plants and is really just about making sure that the smell doesn't esacpe before passing through the fan and filter.
Perhaps consider a an auto transformer (Variac) to reduce fan speed and noise? I've had one for a while and wouldn't do without it now. (Don't get the "dimmer switch" type of controller unless you want a much noisier fan!)