So we are the crazy people who thought this pool would be a good idea. Our backyard had a slope. It also had trees that we decided to cut down. We were very limited on space for where we could put the pool due to ordinances for our garage, fence, house and so forth and that was the reason for the decision. We pulled the trees and used an excavator to remove stumps and start the leveling process. We then determined we needed to do more leveling so we rented a bobcat and my husband who works for a contracting company had his employee come and use it to level the ground. We used a contractor level to ensure it was correct. We assembled the pool and leveled the poles. Then we began to fill. About half way through we noticed that the side where we pulled the tree was sinking and was lower than the other side. We measured and determined it was 3". After reading a ton on here my husband was not comfortable leaving it, so we emptied the pool, disassembled the pool and began leveling again. This time we used a skid steer and rototiller to lower the higher ground. We even went a little lower than the sinking side in case the lower side sunk more. We laid a small amount of sand under the liner only and smoothed out. We then again reassembled the pool and filled. We watched and it seemed level. By the time it filled all the way the sinking side once again sunk and was 2" lower than the side we just dug up but this time it wasnt in the area where we pulled the tree. It seemed this was due to the poles sinking. We decided to use patio blocks after reading more. (yes we are the people who only fix one issue at a time. LOL ugggh!) We emptied the pool and last night began putting the blocks under the legs. My question is this. I am thinking that we need to only put the blocks under the low side to make it higher than the other side in case they sink more. Will the patio blocks still sink? How much will it sink? Does anyone have any suggestions? My main concern is to level the pool and it sink on one side again. We CANNOT do anymore and my 13 year old is already heartbroken as it has been 3 weeks we have been working on this.