when to refill your carbon filter

Tim Fox

Well-Known Member
I ran a short grow thru my wardrobe grow cab, I had a brand new 6" carbon filter, I ran the 2 very small plants thru 9 weeks of flowering, and the filter performed pretty well, considering I grow in my bedroom!, my question is this, does the carbon need to be replaced every grow?, all the carbon filter web sites say thier filters are good for 12 months or more? thoughts? I want to clean up my box and have it ready to start another grow in sept.
 

Dr. Who

Well-Known Member
I posted this in another thread.....it fits here perfectly!

Why throw it out? You can wash and recharge that carbon!

Use a mild biodegradable soap in RO or deionized water. Put in the carbon and swish it around for about 15 min. Drain and rinse, 3 times, soaking/swishing the carbon for 10 min the first 2 times.
Now dry it and bake it in an oven at 250 deg till dry.....The heat does the "recharge" as it dries out. The mild soap removes any accumulated oils that it may have absorbed (only in the surface pores [on the carbon] are where these oils get trapped).

This is how a major drug company does it's lab filter carbon.

Doc

P.S. You might try the oven recharge first as that has good effect if your whole filter fits and you don't feel you want to tackle removing the carbon....Be sure to take off the white "prefilter" first.
 

rshackleferd

Well-Known Member
Go to ebay and type in "5lbs Air Water Filter Refill Coconut Shell Granular Activated Carbon Charcoal"..This stuff last me 18 months.
 

Tim Fox

Well-Known Member
I posted this in another thread.....it fits here perfectly!

Why throw it out? You can wash and recharge that carbon!

Use a mild biodegradable soap in RO or deionized water. Put in the carbon and swish it around for about 15 min. Drain and rinse, 3 times, soaking/swishing the carbon for 10 min the first 2 times.
Now dry it and bake it in an oven at 250 deg till dry.....The heat does the "recharge" as it dries out. The mild soap removes any accumulated oils that it may have absorbed (only in the surface pores [on the carbon] are where these oils get trapped).

This is how a major drug company does it's lab filter carbon.

Doc

P.S. You might try the oven recharge first as that has good effect if your whole filter fits and you don't feel you want to tackle removing the carbon....Be sure to take off the white "prefilter" first.
Thank you, i had forgotten about the oven stuff, that sounds good , I wonder how many times you can wash and bake it?
 

Tim Fox

Well-Known Member
Go to ebay and type in "5lbs Air Water Filter Refill Coconut Shell Granular Activated Carbon Charcoal"..This stuff last me 18 months.
good stuff, i looked at it on ebay, some of those auctions are for 5-10 pounds of carbon with shipping can be almost 3/4ths the cost of a new carbon filter complete on ebay, I see the stuff for fish tanks looks like pellets on ebay , and the coconut shells are really fine, I am guessing the fine stuff filters way better?
 

Dr. Who

Well-Known Member
good stuff, i looked at it on ebay, some of those auctions are for 5-10 pounds of carbon with shipping can be almost 3/4ths the cost of a new carbon filter complete on ebay, I see the stuff for fish tanks looks like pellets on ebay , and the coconut shells are really fine, I am guessing the fine stuff filters way better?
First off....The drug company used theirs for 8 years before a new maint. engineer swapped out for new.....They have some nasty chems that run through it and it was washed every 6 months till the swap.....It was still working perfectly......He just had money allotment to spend before the end of the fiscal year, so the dept. got the same amount next....So I have no idea how long it would keep working,,,,.....sounds like it could be a long time!

The idea of scent control and carbon filtration is to supply as much surface area to the air flow as possible.....Look in your filter and see the carbon size.....You should refill with the same size carbon or as close as you can get (if you choose to replace)

Doc
 

HipChum

New Member
Hey Now Doctor Who, I’m going to try your washing activated carbon method. Does that RO or deionized water need to be warm or hot? Thanks!
 

Wastei

Well-Known Member
Look for activated carbon with a CTC value of 70% and above. Often you will get a better performing filter than new after refilling/replacing the carbon.

Most filters have activated carbon with CTC value of 50%. Industrial classed filters will often last for years if you don't run them at maximum specs.

Nowadays the testing standard is called "ASTM D5742" because of the banning of carbon tetrachloride for testing. But it's being converted to the old CTC standard. Nowadays they use butane to test "porous quality".
 
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calvin.m16

Well-Known Member
I go off smell. If I walk in and I can smell dank then my scrubbers aren't working to par. You could have someone else try to smell for it too. You should have a pretty clean smell throughout your room if you have the proper CFM going through your scrubbers for your cubic airspace. (width x height x length of room).

e.g 10x12 room with 7 foot ceilings is 10x12x7 = 840 Cubic Feet of Air in the room. This means a 750 CFM 8" inline fan should scrub the air once every 2 mins at least.

I basically added up all my cubic airspace and ended up needing 4 8" scrubbers for my spaces. The Can-Lite filters tend to last about a year before you start getting an almost sour smell or drywall smell.. I've had my filters for 2 years running 24/7/365 and they still are working keeping pre-filters changed and grow space clean.
 

Wastei

Well-Known Member
Taking a filter apart and refilling sucks. Without a way to vibrate the carbon, you'll never get it all in.
Sure it sucks. But it can be done. If you do it every second year it's not that big of a deal.

Paying 10 bucks instead of 300 for a new filters makes it worth while for many. Its also a more sustainable practice.
 

HipChum

New Member
Sure it sucks. But it can be done. If you do it every second year it's not that big of a deal.

Paying 10 bucks instead of 300 for a new filters makes it worth while for many. Its also a more sustainable practice.
Where can 5lbs for $10 be purchased?
 

V256.420

Well-Known Member
I replace mine every 12 to 15 months. I use Phresh but they are SOOOO expensive now I don't think I can anymore. I saw that AC Infinity has cheap filters and tents now but who knows how well they work. I can buy two of the 770 cfm 8" filters for less than 1 Phresh 750 cfm one....but are they any good.

If the filters last 8 months each and the 2 are lower priced than the one Phresh that lasts 12 to 15 months it may be a bargain.

Haven any of you ever washed carbon before? Wooohoooo good luck baby :eyesmoke:
 

Apalchen

Well-Known Member
It's gonna be messy even just replacing the carbon, couldn't imagine trying to wash it and bake it. But my filters are big. I have 5- 40" long filters. If your in a legal state I guess you could try it but I still don't see being able to pack the filter as well as the manufacturer. If your not in a legal state then I'd replace with name brand as often as needed. Filters would be equivalent to like an ounce or two at most a year. Def cheaper than a lawyer or bail money.

I'm in a legal state and I will replace them when they start to wear out. I'm much too busy keeping up with the garden to spend a couple days washing carbon and trying to pack it back in.
 
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