4x8 tent ventilation help

ipower and vivosun are both cheap brands and a higher rate of failure is likely.

I had one single one work through 2 harvests. So I don’t thunk they’re that bad tbh

honestly I went with phat love em

How many grows or months did it last @Gond00s

I just moved to it and what I meant I love how it works so far don't know how long its going to last but should be a while bc its in 45%rh

Aviatorshades said:

I had one single one work through 2 harvests. So I don’t thunk they’re that bad tbh

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Yeah 90% of the time they are ok.

The difference between a good filter and bad is quality control on packing of carbon. It only takes a gap and that's the whole thing useless when it could of been vibrated down better and would of been perfect , possibly for a year or two.

I have to go with a trusted and more expensive brand because I cant afford to get busted. But some of my filters have lasted years (10-12 crops per year) and I change them as a precaution rather than waiting for them to fail.

Aviatorshades said:

I had one single one work through 2 harvests. So I don’t thunk they’re that bad tbh

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Yeah but I have vortex fans that have ran for 6 years. I doubt the cheaper fans would last that long. but if on a budget and just need to get a year or two out of them then a cheap fan is a good option to have.

Gond00s said:

honestly I went with phat love em

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Phat and Phresh are the only brands I will use. I have some that have been going for 6 years and they still work!

Renfro said:

Phat and Phresh are the only brands I will use. I have some that have been going for 6 years and they still work!

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Sounds about right

What size phat /phreash filter would you recommend for a 4x4 with 6” fan or a 4x8?

Aviatorshades said:

What size phat /phreash filter would you recommend for a 4x4 with 6” fan or a 4x8?

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What model fan?

There are two CFM ratings for a filter. One for scrubbing (multiple pass / recirculating) and one for exhaust (single pass ventilation).

An over sized filter is always good, can't go wrong there.

Exposure time is the key, with scrubbing the filter doesn't have to get all the odor since it will be continuously filtering the same air. With single pass it has to get all the odor so the flow rate has to be slower to increase exposure time.

So don't exceed the manufacturers CFM rating for the application (single or multi pass).

Here is a chart that can be helpful

http://www.phatfilter.com/what-size-phat-filter-do-i-need

http://www.phreshfilter.com/tools/cfm-calculator

Get a filter that has a single pass rating that is equal to or larger than the CFM rating of the fan.

Renfro said:

What model fan?

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VIVOSUN 6” 440cfm (purchased from amazon. Works well has a speed controller dial built in)

The 6x39 is rated for 400 CFM single pass.

So I could run this medium high fan speed setting let’s say 350 cfm and be good? Not that I’d ever run that high. Temps are never bad enough to do that

As long as the real world CFM doesn't exceed the single pass number in the sizing table the filter will clean the air. If you pull the air through a filter too fast then it can't clean it well, thus those ratings. It is always good to have the largest filter you can fit/afford, over sizing them is good. If you were to get one that is just enough and it loses 10% of it's ability suddenly you have an odor problem. So you are dealing with two factors, can it do the job and how long will it do the job.

If maximum odor control is the goal I like to use two carbon filters and two fans. One as a scrubber, it just recirculates the tent air cleaning it. The other setup is on the exhaust.

The cylinder type carbon filters that are made today are no more efficient than the cylinder type carbon filters that were made 40+ years ago as they are still built with silly cave-man type logic! Yeah, we pay big bucks for a lot of filtering area that won't ever filter even 1% of the dirty air we are wanting it to filter through its entire in-service lifetime! And even the best cylinder type carbon filters still allow for nearly 10% of the odors they are supposed to trap n' eliminate to directly pass-thru the filter. Anyway... if you understand this one scientific fact, that air being pulled will always take the path of the least resistance, then you will understand how truly inefficient all cylinder type carbon filters are. And as a side note... the most efficient carbon filters have a flat inlet surface, and the active carbon used within the carbon filter maintains the same depth, (and that depth is set to match the filtering flow rate adjusted to the fan being used), across the entire filtering plane, and the filtering plane must match the exact size of the cylinder type fan that is being used to pull the dirty air through the carbon filter for a carbon filter to start off at nearly a 100% efficiency rating! Then the only thing that will truly decrease its efficiency is the amount of relative humidity that is in the air!