I am not an installer, but when my liner was replaced a few years back, the guy did put some kind of pink pad down under it and then duct-taped the seams of the pad. The pad was not specifically a pool product, but something that either went behind paneling or inside drywall or ?????? I can't remember. I does make the floor of the pool nicer than without it but one problem I do have now is that dirt wants to settle in those slight indentations where the duct-tape is under there. Not a huge issue and easily vacuumed up but even when I vac every day, any dirt that settles back down always settles in those lines. Does the pad you are looking it come in pieces where you would have to have multiple pieces or is it one large piece that goes down? Maybe one of our members like maybe Waste (a.k.a. Ted) who install liners can give you some advice about this.
Is this your first pool? You're gonna love it!
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