Spring 2015, we bought a used 24'x52" Ultra Frame pool from a neighbor for about $300.
Our land is anything but flat, truth is, we live on a very slippery clay slope so the boss (my wife) and I decided to flatting it out best we could because we needed to hurry up and put up the pool in time for July 4th pool party / fireworks. Initially, the pool worked out great but we didn't do a very good job at flatting out the ground which is mostly clay, so when it got wet, the pool started to slide over until the legs gave way one night and we woke up to an empty pool.
We also found out the liner had some holes in it so we had to buy a new liner, as I was researching ideas on the internet I came across this website and saw where a guy had built a large sand box because he too lived on a mostly clay type soil where it didn't matter how flat you got the ground, w/o some type of sand box, the pool would sink when the ground got wet; probably because when full, it weighs in at about 60-tons.
So, I built a large sandbox and ordered 12-yards of sand, I lined the box with a 30mil pond liner. The sand arrived and I used a shovel to spread it, took about 3.5 hours for me to move 12-yards of sand with just a shovel. Unfortunately, I wasn't thinking very clearly in my execution of this task because I forgot to figure in the slope factor, so after I moved the sand and used my lawn tractor to pack it down we set up the pool and started to fill it. As it filled, it donned on me that something wasn't right because all of the water was going off to one side of the pool even though I had checked level several times while filling up the sand box with sand.
We emptied the one foot of water from the pool, disassembled and removed it. Then, we used the water inside the sand box to tell us where we needed to move the sand to create a level surface for the pool. After that was done, we reassembled the pool and centered it inside the now perfectly flat and level surface of the sand box.
Tried several times to upload a few pictures of our progress but nothing happens when I chose the picture I want to upload.