Let’s get a bit scientific here. They clog up mainly due to the temperature clash. The smoke brings in heat and mixes with the coldness of the activated charcoal. As a result, the humidity and smoke become condensed before they are filtered.To prevent this, you’ll want to warm up your actiTube SLIM filters slightly before using them. A good trick is to place them on a pre-heated surface like a radiator. You can also take smaller hits to slow down the heat-up of smoke.