I have a 1/2" gap below my bottom rails due to how my patio plates/pavers are not fully sunk. The soil here is like digging through limestone ... near impossible ... watch in the video how I have to use the back end of a hammer to scrape away the area for the pavers. The last 3 seconds of this video show how minor the gap is. I have at least 2 tons of soil left from the excavation as well as 4 tons of sand being delivered tomorrow ... what should I do to correct this? Should I backfill with native soil and water/tamp or simply spread the sand just outside the pool wall? Also, since I have a Gorilla Pad for my install, and foam coves, how much sand should I use? I assume the Gorilla Pad goes right over the sand, or is it used instead of sand?