Planted Tank Guru
Join Date: Jul 2010
Location: British Columbia, Canada
I'd recommend quartz-based white silica pool filter sand, which grows plants very well, with the use of root tab ferts. It's very clean, with very little dust or grit, needs little or no rinsing, and easy to keep clean.
It's much cleaner than play sand, denser, usually larger-grained, doesn't get sucked up in a vacuum tube, does not throw off free-floating grains when disturbed, and will not clog up your filter assemblies - whereas most play sands do exhibit these negative characteristics.