Hmmmm, no one has any experience with sand caps for soil?
Pool supply stores carry 50# bags for around 12 - 15$ (I called three places in Vancouver). Lowes has several varieties of sand for 2-4$ for a 50# bag.
I would prefer the cheaper priced sand, obviosuly. But if its going to be more of a pain than the filter sand I should probably go with the filter sand, yes?