I clean my tanks with swabs and alcohol or let the Kanger for example soak in alcohol and then leave them to dry. I have had much success with this. Make sure they are dry! And don't put your wicks in it.
It could be that you didn't let it sit for a bit. Some Ati's have to properly soak up juice or you get a burnt taste. Also, if you aren't waiting enough time between each inhale. Maybe it is getting too hot.There is a lot of good info above, try whatever you think will work.