We had our liner replaced about four weeks ago. cost was just over $3,000. Yesterday my son discovered what appears to be a rock under the liner in the shallow end. It seems pretty sharp and sits about 1/4 - 3/8 inch above the bottom. This discovery has me just sick. I've read a lot of varying advice about how to deal with this. Anything from cutting the liner to remove the stone and then patch it to doing nothing other than observing. I really feel like it is too big and too sharp to try any of the options I've found and I just know that it will eventually poke through. I'm going to contact the company that installed it first thing Monday. I'm keeping my fingers X'd that they will make this right but what do I do if they won't fix it?