We bought a used 15 x 30 above ground pool and I was told to put foam on the bottom of the pool for the liner to sit on it! Pack the sandgood then cut the foam and tape it together then set your liner on top. Any of this sound OK? Or can we just do without the foam? The previous owners had no foam!

We have used a heavy tarp before, many just use sand, Have you went to the manufactors web site and looked up their recommendations.