cyrnel

A box of activated charcoal is about $3/L. Dust-free maybe $7/L, otherwise rinse for 5-10min first.

Cut the top curved part off a 2L soft drink bottle. Put a pinhole or two in the cap. Flip it upside down. Now you have a metering funnel. Put in a conical coffee filter, fill it with a cup of activated charcoal. Set the funnel/filter on a receiving container and start pouring.

1L of activated charcoal is probably the equivalent of 100 brita filters.

Edit: I forgot. Wet another coffee fliter and place it flat across the top of the charcoal. Press a slight depression in the middle as if you were going to fill with gravy. That's where you pour. The barrier disperses the flow and keeps it from passing too quickly over and through the charcoal.

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There are a vast number of people who are uninformed and heavily propagandized, but fundamentally decent. The propaganda that inundates them is effective when unchallenged, but much of it goes only skin deep. If they can be brought to raise questions and apply their decent instincts and basic intelligence, many people quickly escape the confines of the doctrinal system and are willing to do something to help others who are really suffering and oppressed." -Manufacturing Consent: Noam Chomsky and the Media, p. 195