Hey all,
What do you think of this filter? Curious to hear your thoughts. I like small DIY projects and this was pretty fun and easy to make.
It’s about 10" long with an inner diameter of 3" and outer diameter of 6".
I originally thought I’d go with something bigger but realized the pack of activated carbon was only so big, so it was measured to take just that volume of filter media.
Inner is a 3" PVC with holes drilled, outer is just 1"X2"hardware fence, each wrapped with a lightweight landscape fabric and taped. I capped the top and bottom with foam cutouts. Everything was salvaged other than the activated carbon and a 3" to 4" PVC reducer. So it cost me about $30.
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Thats cool mayn
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i tried making a filter, and it worked great.!!
the money spent is not worth it,
filters only work as good as the amount of carbon in them,
you have at most 5 lb of carbon at $30, $6 per carbon pound per filter,
a Can-Filter 66 has 40 lb at $200, $5 per carbon lb per filter.!!
u spent a few hrs building $6 a lb, it will last 1-2 months growing one plant,
i went to the store and got $5 per lb and it will last 6 months.!!!
and i m drawing a lot of air thru my Can-Filters.! (630 cfm Huricane)
if carbon was free, DIY would be the way to go, but it is truly not worth it for a filter.!
u were lucky, i purchased nearly everything for my DIY Pro style ‘20 lb’ filter.!!
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I love it! Seems like it’d work just fine, too. Made me think of that scene from Bio Dome…“makin’ a filter, makin’ a filter…”
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I hear you on cost effectiveness … This is one of those DIY projects that when I finished the job I had to ask “was it really worth my time?”.
Where are you getting those numbers on operating life? I would be really bummed if this filter only lasted 2months.
Can 66 looks like 31lb for $210 before tax so $7.80/lb where I live. But way overkill for my 4x4 grow tent and 150cfm fan. The can 33 would make better sense at 16lb carbon for $140, at around $10/lb.
My filter was actually only 2.5 lb. The carbon alone costed me $12/lb!
Thanks this was a helpful perspective. Where can I find a formula for filter life??
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there is no such formula, too many variables to calculate,
the general rule is more carbon = better scrubbing and longer life.
my numbers come from years of running carbon scrubbers,
do not expect 2 months of use in mid-late flower, even with one plant under 200w,
assuming u r gonna fill the 4x4 with light wall to wall,
800-1000w of HPS/Blurple led, or 480-640w of QB, Optics 1 or Migro COB…
4x4= 16 sq ft x 7’ h = 112 cu ft x 4 (magic factor, lol)= 448 cfm needed, on a speed controller,
a 6’’ HO with a Can-66 would be minimal, Can-75 might be more ideal.!
the ‘magic factor’ of 4x allows your space to exchange air 0.5-2 times a minute while running duct work, filter, passive intake, and air cooled hood.
the 4x could go up or down depending on the variables u have.
i have a new set up, 5.5 sq ft of veg and 5.5 sf of flower, and using the Can-66, hoping it lasts 6 months, if it goes longer great, but not holding my breath.!
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Dude! I love that movie lmao!!! Thanks for that man 
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Is it washed or did you wash it? You really need to. Having washed literally thousands of pounds of charcoal for polishing vodka I can say it’s a really good idea to wash beforehand.
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I went the simple rout on mine
I used a 17/64 bit to drill out the back rivets
I boiled the carbon prefilter inside for reuse. Then I dump and replace the charcoal inside. I’ve been considering using some landscaping fabric to replace the prefilter on the 3rd use.
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That a good way of doing it I was of thinkin if doing something like that but I was also think wat if I put that charcoal in my old filter wat I use b4 the 6” one but I will have too put in side the hole small lumps but cover the hole so it don’t mess up my fan is that a possible peps wat u think
(flowering has started)Just an FYI / update for the greater audience. My carbon filter is still doing great! I’m in the tail end of my second grow. First grow was 2 plants with 200W light, 2nd grow is 4 plants with 400W light. I’m in the 6 month range in terms of run time with this DIY filter. Mind you this is low THC (6%) high CBD weed so maybe the stronger dank weed does more of a number on the air filters!
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