Hi. We had our pool put in four years ago. It was installed in Oct so we didn't swim until the next summer. When we got in I noticed bumps all over. I called the pool company and they came and pulled back the lining and there was pea gravel all over. Long story short-over the last four years they have taken the liner out and cleaned it off several times. Last year they drained the pool and re caulked the seems and put a new liner in bc the first one had holes from all the pea gravel. Then comes this summer and it is back. I already have one hole and another starting to bust through. The pool company came out and said they don't know what is doing it and seems they aren't going to fix it anymore. This has been a problem since our pool was installed. Any help on what could be causing it? I can't replace my liner every year. I will say-since they re sealed the edges it does seem better but isn't completely taking care of the problem.