Looking for a carbon filter!

brotherjericho

Well-Known Member
I've had a Phat filter in my flower tent for 14 months, can't smell anything. I even have a port in my exhaust I open to check periodically for escaping odor so I know when to replace. I typically flower 3-4 plants at any time, so its been doing great for all this time.

http://www.hydroponics.net/c/566

You can get the 4x12 for $52.46 plus shipping. It does say 3-5 days for shipping (time from their store, not total), and I've found that to be pretty accurate whenever I've ordered from them (four times thus far).
 

roesn

Member
This is the exact filter I run. Installed correctly, it takes the stink out of ANYTHING. I have a skunky Critical+ in my tent now that will absolutely RUIN the air quality of the room when I open the tent, but with the tent kept closed, no odor at all. I trust Phresh with my life and freedom.
Great. So I should get that filter along with the 190 CFM inline fan? (with controller)
 

whatsupdoc

Active Member
Great. So I should get that filter along with the 190 CFM inline fan? (with controller)
You want:
A fan that approaches but does not exceed the 190 CFM rating of the filter (a bit noisier, but cheaper)...
-OR-
A fan that exceeds the filter rating, but uses a fan controller to reduce speed/CFM (quieter, but more expensive).
 

roesn

Member
After some research, I plan on going with this combo.

Phresh Filter 6" x 16" 400 CFM w Flange Carbon Can Odor Control Inline Fan
6" Inch 440 CFM Hydroponics Inline Duct Fan Exhaust Blower Vent
with Fan Speed Controller

I will never run the fan at 400 CFM, it will be around half power most of the time, but the larger fan should allow me some temperature control and ensure that my 600w HPS is cooled.

With 4 plants, how strong will the odor be with that fan and filter? Any estimate? I dont know how much odor to expect outside of my grow room during flower...

 

turnip brain

Active Member
For just air exchange in the grow space your airflow is around 15-20x times too high. You want air changes more like one every 5 minutes and no more than a change every 1-2 minutes, Higher rates cause stress to your plants: Ventilation 101:https://www.icmag.com/ic/showthread.php?t=112862rather than 4 every minute. For a 40 cuft space, you should be looking at 8-10 cfm actual flow. You do not have to push the rated cfm through carbon. Slower flow is just fine.

I just went through all these design considerations for a 59 cuft space, and came up with a two fan setup, one 4" S&P TD100 for the fresh air and carbon filter, and one 5" TD125 for light cooling. Only the 4" will circulate air through the grow space and carbon. And, both will be dialed down to minimum fan speed to do the job.
 

texin

Well-Known Member
I use a 6" 400 cfm Phresh filter for a 4x4 room they are very good no smell out of the tent. Thats all I will run is phresh Filters
 

roesn

Member
For just air exchange in the grow space your airflow is around 15-20x times too high. You want air changes more like one every 5 minutes and no more than a change every 1-2 minutes, Higher rates cause stress to your plants: Ventilation 101:https://www.icmag.com/ic/showthread.php?t=112862rather than 4 every minute. For a 40 cuft space, you should be looking at 8-10 cfm actual flow. You do not have to push the rated cfm through carbon. Slower flow is just fine.

I just went through all these design considerations for a 59 cuft space, and came up with a two fan setup, one 4" S&P TD100 for the fresh air and carbon filter, and one 5" TD125 for light cooling. Only the 4" will circulate air through the grow space and carbon. And, both will be dialed down to minimum fan speed to do the job.
Well I was planning on running the fan on low/medium so it could run quieter. Also getting the 6" size instead of the 4" for the fan and filter save me some hassle in the cool tube/exhaust set up.
 

turnip brain

Active Member
Well I was planning on running the fan on low/medium so it could run quieter. Also getting the 6" size instead of the 4" for the fan and filter save me some hassle in the cool tube/exhaust set up.
Understand. I considered the same, but decided that independent control would allow better control over the grow for both temperature and air exchange. And these fans are a lot quieter in the inline category.
 

roesn

Member
Understand. I considered the same, but decided that independent control would allow better control over the grow for both temperature and air exchange. And these fans are a lot quieter in the inline category.
Ok so what do you recommend I do? And by "independent control" do you mean have 1 inline fan to cool the light and have another fan to pull air through the carbon filter?
 

raven1290

Active Member
It will give you even more control running 2 fans, 1 for the filter and 1 for your light, but also more money and a little more work in setup. As turnip brain said, it's up to you how you want to do your setup. Unless you plan to upgrade to a larger grow area in the future, I would go with a 4" fan and filter as you original planned. I actually run the small 4x8 Phresh filter and have no odors. You can put your nose up to my exaust and the air is fresh and clean. I run a 400w light, so with a 600w light and depending on the rest of your setup, you may need to run your fan at a higher speed than me and therefore may want the 4x12 filter. There's not much of a price difference between the 4x8 and 4x12, but the 6x16 is a good bump in price. The 6" fan from gotham hydro is only an extra $8 over the 4" and running that a lower speed vs the 4" at a higher speed may be a bit quieter, but I can't be sure on that. The size of the filter doesn't relate to how much odor it can handle, but more to how much air it can process at once. So a person useing a larger grow space would be running a larger fan with more cfm and require a larger filter to effcienlty handle the higher airflow. As long as your fan is not pulling more air through the filter than the filter is rated for, the filter will take care of all the odor. That is ofcourse assuming you use a quality filter. As said, I use Phresh so I can personally recommend them, but Can, Mountain Air, Phat and Rhino all seem to get equally good reviews.
 

roesn

Member
Great. I will continue looking at different filters and might do the 2 fan set up. If I do this should I get 2 of the same fans with 2 fan controllers?

My grow box is 50 square feet and the fan that I found that is 190 CFM (picked this for the 200 cfm 4x12 phresh filter you recommended.) But in the description it says this.

[h=1]1) How much space can this 4" Inline fan handle?[/h] When used for ventilation, a 4" Inline Fan is a good fit for a space up to 6' x 6' (36 square feet)
Do I need a bigger fan? My box is 50 square feet and I dont want to cheap out on a carbon filter. I want the odor 100% gone. So do I need more to control the odor 100%? Or will this already be more than enough power to clear the odor?
 

raven1290

Active Member
Did you change the dimentions of your grow space? If not, it's not 50 sq. ft., it's only 8 sq. ft. or 40 cu. ft.
 

roesn

Member
Here is the current design. Not all of the hardware is up to date though. Might go with the 4x16 phresh 200 cfm + 190 cfm 4" fan if its enough.

Untitled.jpg
 

roesn

Member
It will give you even more control running 2 fans, 1 for the filter and 1 for your light, but also more money and a little more work in setup. As turnip brain said, it's up to you how you want to do your setup. Unless you plan to upgrade to a larger grow area in the future, I would go with a 4" fan and filter as you original planned. I actually run the small 4x8 Phresh filter and have no odors. You can put your nose up to my exaust and the air is fresh and clean. I run a 400w light, so with a 600w light and depending on the rest of your setup, you may need to run your fan at a higher speed than me and therefore may want the 4x12 filter. There's not much of a price difference between the 4x8 and 4x12, but the 6x16 is a good bump in price. The 6" fan from gotham hydro is only an extra $8 over the 4" and running that a lower speed vs the 4" at a higher speed may be a bit quieter, but I can't be sure on that. The size of the filter doesn't relate to how much odor it can handle, but more to how much air it can process at once. So a person useing a larger grow space would be running a larger fan with more cfm and require a larger filter to effcienlty handle the higher airflow. As long as your fan is not pulling more air through the filter than the filter is rated for, the filter will take care of all the odor. That is ofcourse assuming you use a quality filter. As said, I use Phresh so I can personally recommend them, but Can, Mountain Air, Phat and Rhino all seem to get equally good reviews.
Does the size of the filter change how well it cleans odors? Like the thicker the filter the better it clears the air. So would a 400 CFM 6" phresh filter clean the odor better than a 200 CFM "4 phresh filter? Or is it the same but the only difference is that the 400 CFM filters twice as much air as the 200 CFM (but not any better) Correct? I have read a few threads about carbon filters but have never purchased one..
 

raven1290

Active Member
Yes, a larger filter simply processes more air at once. Carbon thickness is the only thing that matters as to how well a filter removes odors and this is the same on all Phresh filters.
 

roesn

Member
Great. I will get the 400 cfm just for extra power :) Do intake filters have to go on the out side of the box or could they go on the inside too? Might pay the extra 8 bucks for the intake filter
 

mkbinc1971

Member
roesn, check out Mountain air filters. My sale's guy at store turned me on to them,works great and is cheaper than others and has a 3 yr. guarentee.Use 2 use Phresh,but no more! I run A.K,W.Russ, Blue widow, Blue hash, Pinnapple Express, Critical jack herer & Sleestack and you would never know it!
 
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