I removed the most inner cylinder and put a custom tube in instead making it much shorter and pushing it farther in to the bottom to disrupt the stupid vortex action. Then i modified the MJ1200 to take in air without the venturi action (so much higher flow and a lot more bubbles get in). Now it is skimming a ton with having the air flow at lowest setting. I looked up online for mods but this is my own way after playing around with it a hundred times to find the right length of the most inner tube. Took me all day to figure it out.