Hi my name is Eric. I just got my first Vape which is kangertech. Not sure of the model but it cost $50. I'm using 6mg juice. Will my tank is full the hits are smooth and produce a lot of smoke. But as the tank begins to drain, it gets harsh and less smoke is produced. Even when the tank is 3/4 full this begins to happen. But if I pop it off it begins to get harsh. I have my wattage set at around 30. Any suggestions?