Passive Intake

[iShatterBladderz]

After much advice from the users on here, I decided to return my intake fan and run passive intake. What I finally decided on, n my 4x4 gorilla grow with 480w QB, I will still be using my AC Infinity t6 fan as my exhaust, connected to the temp/humidity controller, running on smart mode (always running, but adjusts the speeds up and down based on temp/humidity), I will be using a 6x24 phresh filter, thats rated up to 275 CFM one-pass filtration (550 Max CFM) mounted right in front of the exhaust port in the top back left of my tent, with ducting going to the fan on the outside of the tent.

For passive intake, this is where I now could use some help, I for sure will be using the duct port diagonal to where I’m exhausting from, I planned on running 10” 4-layer ducting from the bottom front right port into an s mounted on the side of the tent, with pantyhose as a filter. Now I have seen people saying everything from twice the exhaust size to four times the exhaust size. If that one 10” port will be sufficient, that would be ideal. If not, I‘m stuck between three options, as I want to avoid using the vent flaps. I could run a second run of ductingfrom the port in the top middle of my right wall, if I did that I would run the ducting along the inside of the tent so that it the air is still coming into the tent in the same spot my first intake is. If I did this, I would use 6” ducting. This isn’t ideal for me , but I would like to keep directional airfloW. My last option would be to run a duplicate version of my first intake on the opposite side, front bottom right, with 10” ducting, giving me nearly four time the size of my exhaust.

thanks again for all the advice

 

[BigBallzWillie]

The 10" is enough intake for a 6" fan. Instead of putting any pipe inside the tent for the intake, I made a light baffle out of a cardboard box and attached it to the tent's lower intake vent on the outside.
Important that your exhaust piping is 6" all the way. I have one tent with a t6 venting through a 4" pipe and performance is less than the t6 I have going in a 6" all the way out.

 

[iShatterBladderz]

The 10" is enough intake for a 6" fan. Instead of putting any pipe inside the tent for the intake, I made a light baffle out of a cardboard box and attached it to the tent's lower intake vent on the outside.
Important that your exhaust piping is 6" all the way. I have one tent with a t6 venting through a 4" pipe and performance is less than the t6 I have going in a 6" all the way out.

Yeah, I planned on using the 6” ducting throughout the whole exhaust line. 10” will only be used for the intake. Thanks, it was actually your comment that got me looking into active vs passive intake. I’m glad 10” is enough because I really didn’t want to have to mess with running a second intake.