im using a tank from smoketek with a 1.5 ohm carto that are pre punched with tiny holes. and for some reason after a while of using my pv it get really hard to draw and cloggy and i take my drip tip off and the carto is full of like dark juice and my juice is not dark its almost completly clear anyone know why this happens and if you can just blow the carto out and reuse it or do you have to throw the carto away and try again it seem to happen every time