Backfilling is an important step in the fiberglass pool development process. This is whenever you refill the areas across the perimeter of the pool with dirt, rocks, gravel, or sand. At the same time, the pool will slowly be full of water to equalize the strain on the fiberglass pool shell’s floor. Step 6: Mark The Pool Layout And Start Excavating Und http://pandora.nla.gov.au/external.html?link=https://progorki.com/pool-equipment-systems/