Five years ago when my well pump went out the well company service man tried using the boom to pull the old one out and it became jammed in the well. He then installed the new one above the old one. Everything seemed to work great but now we are getting flecks of debris in the screens of our water fixtures that plug the screens. Less than a year ago we had a new hot water system installed, we went from a tank to an on-demand, that is actually when the debris started showing up. We contacted the plumber and they came out and installed a small water filter between the pump and the pressure tank. We still get debris in the screens. My questions are, was this ok to install the new pump with the old one still in the well casing, what could this debris be and where could it becoming from?