You might want to try a coarse screen for the top side or run the Herbalizer without the top screen. If you're just running straight concentrates then you don't need the top screen. EDIT: What is likely happening is your concentrate pad is floating to the top of the chamber and soaking your top screen with concentrates. The same thing can happen to your bottom screen as well. I would suggest using both concentrate pads and a very small amount of concentrate in the middle of them like a sandwich. If you find that you need more you can always add another small piece after the first one, the key is to avoid getting the pads absolutely saturated. this method in combination with what I said above should help.