On Saturday, August 29, 2015 at 11:26:07 AM UTC-5, Don Y wrote:
In this
case, it was NOT the tubing that failed but, rather, the plastic
"cap" that mates the tube to the bottom of the tank; it snapped
resulting in that end of the tube being "exposed".

This happens when you over-tighten the plastic...which is meant to be hand-tightened.