Bingo! ++Plus rep!go to the pet store and wal mart. grab up a carbon filter cartridge from wal mart for a air purifier, i think its a universal thing that you cut to size for your unit, its basically a green scrubby pad made out of carbon fiber.
something like this
http://www.walmart.com/ip/Whirlpool-Charcoal-Pre-Filters-Small-4pk/19426870
then get some of this
http://www.amazon.com/Filter-Coconut-Granular-Activated-Charcoal/dp/B00GKVNI8E/ref=sr_1_16?ie=UTF8&qid=1408136378&sr=8-16&keywords=charcoal filter refill
open up can and use a shop vac with a filter to suck out the old carbon, then insert the filter (from wal mart) into the can,
something like this
then pour the activated carbon in the middle...the reason for the inserts is to just keep the activated carbon from coming out and it also gives a little more odor protection.
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