1 1/2" styroform v sand bottom

[ShelleyAnn]

The person we bought the pool from told us we had to have whatever we used at just the right height for the beaded liner to fit properly. I'm wondering how you get the liner at just the right depth for the bead to fit in at the top, without any wrinkles when it says to add 2" of sand OR 1 1/2" of styrofoam. Is the liner that forgiving?

[Sherra]

Possibly because sand will compact down about a half inch once the weight of the water is added and the styrofoam won't compact under the weight of the water? Just an uneducated guess.