Carbon filters suck!!!

RB56 said:

Completely unscientific thought. I've had it in my head that a carbon filter should only last 1 - 1.5 years. Pretty sure I've seen the same posted here and elsewhere.

I have had a carbon filter fail after 18 months - the first one I ever bought. It was cheap junk with very little carbon in it. Instead of there being a device related law - failure in 12-18 months, it seems possible that longevity is determined by the volume (surface area, I guess) of the charcoal. So 5 times the charcoal may mean 5x the lifespan.

Just from what I've seen related in this thread, I'm going to adjust my thinking to this: A good filter could last 5 years or more, especially if it's given the reverse air blow out after every few grow cycles and cooked every few years. After that, replace the charcoal. Certainly better than buying new ones every year.

Click to expand...

Being the cheap bastered I am I have tried to bake it a few times, it's a long process unless you have a large comerical oven available,or a single small filter, and it's pretty cheap to replace. I no longer try to bake it ,also just a heads up it stinks really bad when your baking it .

Well since it turns out that we are basically in agreement, let's argue about which one of us is the cheapest bastard. -granger

reactivation only works on certain types of foulants and on certain types of activated carbon.

moreover you need to hit like 1500c to really re activate the carbon and form new cavities.


just buy new vapor phase activated carbon.

make sure you buy the right shit, not the alumina mixtures, and make sure you get the right size.

activated carbon relies on a certain EBCT for fluids and vapors... if you get granuals that are too large the contact time is too low and you dont achieve proper treatment.

if the contact time is too high... you get good odor removal, but at the expense of unnecessary static pressures.

you want the contact time reccomeded and not much more.

Sounds like the bake is out, so use and blow out for a few cycles and replace charcoal. Thanks.

RB56 said:

Sounds like the bake is out, so use and blow out for a few cycles and replace charcoal. Thanks.

Click to expand...

That's what I'm doing. Just ordered my charcoal.

Old thread but I must throw in my knowledge for future noobs.

Almost all carbon filters (no matter which brand) come flawed from the factory. The problem comes from the connection ends not being compressed or sealed tightly, this causes the filters to have a small gap where the carbon is losely held on the ends, allowing unfiltered air to pass easily. I found that once the filter was properly connected/sealed, all air will pass thru the carbon and come out 95% scrubbed ( remainder 5% only for dog noses).

The only thing I smell out of carbon filters is a yeast/bread smell. An A/C kicking on can throw off the negative pressure of a room. Anything blowing in is going to mess with the pressure. Only blow out of the room/tent and use passive intake.

If I did a room, I would have the a/c outside of the room, cool air being passively drawn in. But I don't have a whole room.

I'll never use charcoal again

So what do you use Dave?

They are high efficiency particle filters the grow shop sells locally. I can't say that they come in massive sizes but they scrub the air & don't have a dead spot @ the end that fails. They're light & they cost about £35 for that 6" Edit; It might even be an 8"..

The humidity don't seem to compromise these filter papers as much & you get 0 of that yeast smell.

Trouble is I can't remember the name of the manufacturer of them & it's not inscribed anywhere but for the years we been using them @ a mates they haven't failed us. We use a few in his 24x10 to scrub.

I've had good luck reducing smells with carbon. Key is growing in a room dedicated just for that. I'd really like to have clean air just outside of that room as well. Maybe we can just have legal herb and forget about scrubbers? It'd smell like heaven everyday.

I run two Phat filters the 450 cfm ones with a 6" inlines on each. They sit in my room recirculating with no ducting on them. The room is 12 x 15 with 4k 'sealed'. I say sealed like that because I know the 2 duct portable ac no matter how hard I try is leaking some air which causes positive pressure and some air to leak out. I was getting some major smell leakage outside from the ac exhaust so I installed a big blue 2 bulb inline ozone generator on the air conditioners exhaust. I sealed up that ducting as good as I can but if I turn on both ozone bulbs I get a faint ozone smell in my room. This has caused no negative effects on my room this far.

ozone works great but it has its own distinctive smell. I'd get a cheap ebay one and put it on a timer to come on just long enough to knock the smell down to help the filters keep up. I've not seen any issues with ozone right in the grow room but as I mentioned the amount I'm using in my room is whatever little but leaks from my unit that is installed to duct outside. a little seems to go a long way I bet 60-second cycles a few times a day to kick back the smell would have zero effect on your plants, help your filters keep up and completely fix your problems.

I had a 4k room with 3 can 100's and i had way more smell than with just 2 phat filters that have about 1/3 the carbon inside of them.