My TC is way over 10. I was advised to add 30lbs of shock to bring the level down so that the FC and TC equal themselves out? make sense? anyway, my pressure has gone sky high and the filter seems to be making this knocking noise. The granular shock was diluted before I added it to the pool. It seemed an awful lot of shock to add but was assured this was what I needed to do to get the TC down?? is this normal and do I need to worry about my guage going over 20? the filter was clean before I started this process. It also seems to me that it will take days to clear.