Activated carbon filters
Activated carbon filters are built into exhaust-air plants of growboxes to filter unpleasant odors from the air. An activated carbon filter has to be connected to an exhaust air tube fan, which sucks the air through the carbon filter. That way, the sucked in air has to pass the charcoal that resides inside the carbon filter, which leads to smell-causing molecules being linked to the poriferous activated carbon. Thereafter the air exits the growbox purified and odorless.