Carbon is
the most widely
used chemical filtration.
It is
highly
porous and adsorbs heavy metals, odors, colourants, organic contaminants, pollutants and medications
from your aquarium water.
It will also act as fine filtration of the water column and improves water quality.
This media does have a limited lifespan of around 1 month
before needing
to be replaced, if it is left too long, it can leach the
adsorbed chemicals back into
the aquarium.
Carbon can have some negatives such as
removing beneficial nutrients from the water.