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Pinktiger777
Well-Known Member
And I use smaller cans.
How long does a carbon filter last?
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The recommended minimum is to exchange all the air in your grow space is once every three or five minutes, depending on your source. Personally, I think twice per minute is a minimum for grow tents, as they are much more confined than a room. That's why I have a 6" (150mm) 347CFM fan and 6" (150mm) X 20" (500mm) 441CFM filter in a 2' X 4' X 7' (56 ft^3) tent. I usually run it at about half speed for two exchanges per minute. If the heat or humidity in the tent gets too high, I'll increase the speed of the fan. It helps.
[ QUOTE="Pinktiger777, post: 4436376, member: 279956"]I have a 6inch fan 440 cfm for a 2 x 2 x 6 ft tent.[/QUOTE]
Which should be well beyond what you'd need for a space that's only 24 ft.³ - but that's the fan; what is the filter rated for? I'm guessing that you're fine (in that regard), and that you have some sort of filter designed for a 6" diameter duct and are running your fan well below its rated maximum speed. But that's just a guess.
Old Salt shows that his fan's rated capacity is less than the rated capacity of his filter, meaning that his fan should not be able to "outrun" (so to speak) his filter, even when that fan is running at 100% rated speed. Which, again, is the way to go - and most people do - but I have seen setups where the opposite was true, the fan was moving a greater volume of air than the filter was rated for, and this sometimes caused issues with escaping odors when the fan speed was turned up to maximum (or near it).
Which should be well beyond what you'd need for a space that's only 24 ft.³ - but that's the fan; what is the filter rated for? I'm guessing that you're fine (in that regard), and that you have some sort of filter designed for a 6" diameter duct and are running your fan well below its rated maximum speed. But that's just a guess.
Old Salt shows that his fan's rated capacity is less than the rated capacity of his filter, meaning that his fan should not be able to "outrun" (so to speak) his filter, even when that fan is running at 100% rated speed. Which, again, is the way to go - and most people do - but I have seen setups where the opposite was true, the fan was moving a greater volume of air than the filter was rated for, and this sometimes caused issues with escaping odors when the fan speed was turned up to maximum (or near it).
LOL, I once had a cannabis plant growing in one of the huge concrete planters that flanked the entrance to my local police department. It got large enough to notice. And remained... and remained. I was starting to wonder if they were going to let it go until harvest when it finally disappeared
.And I always wondered if it was cut down and disposed of - or carefully transplanted to another location.
I wouldn't have the... I don't think I'd ever do that again. But it was pretty funny at the time.
The filter material is just activated charcoal. Just scatter it around the yard, it'll be good for it (IMHO). I remember Mom mixing a little in when potting up regular houseplants when I was a little 'Soul.
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Pinktiger777
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My filter is a 6 inch rated above the fan.
Bud
Well-Known Member
How big a filter are u talking about? I’ve seen them 4’ tall and as big as a garbage can? I’m using a 6” carbon fiber scrubber with one end covered,I just reverse ends. Sometimes u have to drill out the rivets to do this,if not screws ( very easy ) to do, and extend the useable life of the filter x 2. I’m a cheep S.O.B. And I explore all possibility before spending. The whole thing took about 15 min. To do.Growers luvThat wont work on the big can filters... only one end on them.
Emilya Green
Well-Known Member
I don't have the really huge ones... but mine are 26" tall and a foot in diameter. I think there is 16 lbs of carbon in there? I can see how reversing the ends on yours would work for a while, but carbon can only hold so much crud before it no longer filters. Dump that carbon out next time you open it up and do a quick cleaning and reactivation... it will be like a new one.
Bud
Well-Known Member
Thanks for the heads up,I may go that route when the smell returns again it’s been two years now wit a perpetual grow going. I reversed the ends a year ago. I know it’s got to give out sooner or later as most thing do, but I’m taken back by the length of time its been problem free and in service.
Emilya Green
Well-Known Member
I am betting that if you attempted to again reverse it and go back to the original configuration after this side wears out, that it wouldn't work. The carbon would be done... all filled up.
So this tells you that in normal operation, at the speed you are running it, you only effectively use half of the carbon... by the time the air gets half way through it is already cleaned. That is an impressive filter! I can push air through this one instead of pulling it in, and get a little bit of extra use out it, but its not the same as reversing it like you are doing... that is cool!
So this tells you that in normal operation, at the speed you are running it, you only effectively use half of the carbon... by the time the air gets half way through it is already cleaned. That is an impressive filter! I can push air through this one instead of pulling it in, and get a little bit of extra use out it, but its not the same as reversing it like you are doing... that is cool!
Mine lasts over two years pretty easily. It’s got somewhere between 80 and 100 pounds of carbon in it and is a bit of a nightmare to hang so I tend to avoid changing it.
Emilya Green
Well-Known Member
I bet it is... how big is it??
Something over 4’ long. 16-18” diameter I think. I inherited the thing ages ago- have considered cutting it down to half size but never got around to it. I have a pulley system on the ceiling but it’s still death defying manoeuvring it up there.
Emilya Green
Well-Known Member
yeah, that's the big one. I would need a crane! I need help or well thought out science to get these up there, and I do hate changing them out.
Bud
Well-Known Member
I never thought of changing it around again... I don’t think it would work. But it goes to show that a filter is only half used up when u can smell pot.You can also wrap Plastic wrap around the first half of the filter and let the air flow thru the lower half using all the filter up without changing ends. My opinion but it does work.
It’s why I was more inclined to try out the boiling in the huge cauldron trick first, before the oven baking trick. I boiled it all in only two batches. If I do it in the oven I’m going to take the oven out in the yard first cause the fumes definitely smelled all wrong.
