does it matter if I use the GE silicon II? I've got some. I used all the silicon I when I resealed the tank. I doubt that about 1 square nanometer of contact with the water will matter, but I thought I should check.
The black piece is the intake stem adapter cover and is part of the filter. It goes on the end of the intake stem (U-tube) with the ridged portion facing UP. This end goes into the filter compartment. When you want to adjust the flow rate, you pivot the intake stem (U-tube) left for full flow and right for reduced flow.
There have been some issues with cracked U-tubes lately so you might have a defective one.
Also make sure the unit is level using the leveling device. Unplug the unit briefly and then plug back in. All the air should evacuate from the filter quickly.
The only other things to look at are: Is there an air stone nearby? What is the water level of your tank? Also make sure the unit is completely full of water before plugging it in.
