I have read many of the threads on here and other sites about sand vs gravel vs free flow for a fiberglass pool. However, most seem somewhat dated so I was looking for any recent thoughts about is sand OK for backfill of a fiberglass pool or is it an absolute must that gravel or free flow be used? Any ideas of the cost difference between sand and gravel? I realize it varies by location so I am in Illinois if that matters.
What about the "base/floor"? Should that be gravel as well or is compacted sand acceptable?
Very new to all of this, so appreciate any response! Thanks