Right size fan/carbon filter?

So I'm currently coming to an end of the things I need to start my growing experience which would be the fan size and carbon inline filter size to fit needed for odor control. I've done some research and keep coming up confused because I'm getting different cfm's. My tent is currently 5x9x6 (5 feet wide 9 feet long 6 feet high). I did the math that was given which was 5*9*6=270 then divined by three for exhausting every three minutes comes to 90. I'm running about 2100 actual watts of LEDs and what I've read is to add another 6-7% for ever 1000watts so I added 14% which came out too 102cfm? Now if I go to Phresh's website and plug all my info in (length, width, height, number of lights) it says I need about 840 cfms. So you could say I'm a little confused and a little frustrated since this is the last thing I need. Haha. So any help would be great appreciated!! Happy growing!

Get a nice 8" filter and fan and a speed controller.

Thanks for the reply! Do they all come the same cfm or should I just get an 8 and call it a day?

I'm sure there's a lot of variations out there, I just went on Amazon and chose the least expensive with best reviews. I bought it filter/fan combo so it had all the parts needed even the speed controller. I'm running it 24/7 in a 3' x 6' closet on the lowest setting and its great. It's probably even overkill, but I didn't feel like the hassle of returning it for a smaller set-up.

I took your 270 cfm and added 20% for 2k LED (54 cfm) and 20% for scrubber (54 cfm) and another 10% for ductwork (27 cfm) and got a total of 405 cfm. Divide that number by 3 to get 135 cfm minimum. So I guess that would be my guess.

that1guy1388 said:

if I go to Phresh's website and plug all my info in (length, width, height, number of lights) it says I need about 840 cfms.

Click to expand...

You entered 5 lights? I entered 2 (for 2kw) and got 390 cfm requiring a 6 X 16 filter. Now I'm confused.

Multiply by 3, not divide

Timezone said:

I took your 270 cfm and added 20% for 2k LED (54 cfm) and 20% for scrubber (54 cfm) and another 10% for ductwork (27 cfm) and get a total of 405 cfm. Divide that number by 3 to get 135 cfm. So I guess that would be my guess.

Did you enter 5 lights? I entered 2 and got 390 cfm.

Click to expand...

Correct, I entered 5 lights at the website so 5x9x6 plus the five lights and got the 840cfm.

madra said:

Multiply by 3, not divide

Click to expand...

So are you saying the 840cfm is spot on or close?

madra said:

Multiply by 3, not divide

Click to expand...

Multiplying would change the air 3 times a minute. I thought that that1guy1388 wanted to change the air every 3 minutes and thus divided.

that1guy1388 said:

So are you saying the 840cfm is spot on or close?

Click to expand...

Close enough to do the job imo

I’ve read some people run them 24/7 at maybe half speed via controller or have it run on a timer for example ever three minutes or so. Just figured the three minutes would be better I’m always open to suggestions/experiences. Thanks!

Depends how important it is to have clean, non smelly air. I would call that a bare minimum if your going for stealth.

Keep in mind the more bud you grow, the more smell is being produced, the more filtering it needs.

Buy a fan bigger than you need and a controller to dial it down, I find the larger fans are more reliable and quieter than the smaller ones (once dialed down) and run it 24/7

growingforfun said:

Depends how important it is to have clean, non smelly air. I would call that a bare minimum if your going for stealth.

Keep in mind the more bud you grow, the more smell is being produced, the more filtering it needs.

Click to expand...

It's definitely important so I would need something adequate to keep the smell down. It is legal where I live and I'm not breaking the law its more for nosey neighbors to be honest.

I was thinking like mentioned above probably a 8in fan with a 8 inch filter?

Id nearly go next size up, its a decent size room you have by the measurements

madra said:

Id nearly go next size up, its a decent size room you have by the measurements

Click to expand...

So 10in on both the fan/filter?

that1guy1388 said:

So 10in on both the fan/filter?

Click to expand...

Yes, bigger is better, less chance of needing to upgrade in the future too.

that1guy1388 said:

It's definitely important so I would need something adequate to keep the smell down. It is legal where I live and I'm not breaking the law its more for nosey neighbors to be honest.

Click to expand...

If it's important then more or bigger is always better when filtering. I'm personally using 3x 8 inch filters for something very close in size to what your doing.

I've had several friends who's house was broken into and crop jacked. People breaking in have had guns. It's a situation I do my best to avoid..
A few years ago when i didn't care as much about filtering I'd have people snooping around at night..

growingforfun said:

If it's important then more or bigger is always better when filtering. I'm personally using 3x 8 inch filters for something very close in size to what your doing.

I've had several friends who's house was broken into and crop jacked. People breaking in have had guns. It's a situation I do my best to avoid..
A few years ago when i didn't care as much about filtering I'd have people snooping around at night..

Click to expand...

Oh wow that’s crazy! Definitely don’t want that. Granted I live in a community of older folk but that doesn’t mean some random might show up and take a sniff and smell it and decide to break in. I appreciate all the help from everyone that’s commented thanks!