I've read the old post about loose flagstone. I had my pool built 3 years ago and within the first year 40% of the cooping and top of jacuzzi flagstones came loose. I convinced the builder to come back and fix it, well they did and it looked worse. Today the stones they reset and many more are loose, a few on top of the jacuzzi I can just about lift off. So, i had a good friend who is a pool builder look at it and he said, it was done wrong and you shouldn't be having this problem. So, I have been reseaching ways and ideas of repairing it my self when I decided to send the builder an email explaining the situation. An old post from the this forum someone replied on this same problem, "call them out". I used to own a contruction company and when I would bring a problem up with my subs they would reply a lot of time, "its OK!" No its not ok, what happened to quality work these days? So, lts see how the builder replies! Thanks for this site!