why is my piece clogging?

Your piece can clog for many reasons

1. It is dirty.  When was the last time you cleaned it?  Using the plug from the Super Soaker will allow you to plug a 10, 14 or 19mm female joint.
2. If you are using it for concentrates it is best to have larger holes.   The oils hit the water and cool to the small holes, clogging it.  Look for a rig with larger holes.   This is also good for flower