New Member and getting ready to install.

Greetings all,

Just wanted to say hi and thanks for adding me to group. I am a new AG pool owner and and starting my install this weekend. I had a quick questions concerning ground prep and under-liner prep.

We purchased a Yardmore 18 x 33 x 54" AG pool from Pool factory and I have the ground completely level with using bobcat and laser transit. I am getting ready to start placing the middle supports and the patio blocks under each of them. The first questions I have is that the install video shows the bottom tracks as just laying on soil between uprights but the installation manual for the pool lists a step regarding placing a 24" border of fine mortar around the pool footprint for the rail to sit on. Is this an either or thing or do I need to do this screed run?

The second question came up after trolling these boards for a few days doing research and it involves the under liner placement. I see some people using 1 1/2" foam board instead of sand. The sounds like an option I would like to do instead of sand. I did purchase a premium under liner pad that the pool company recommended.

Any help or advice would be much appreciated concerning these matters.

Thanks again and I am happy to be part of the group.

Scott