Ive been doing a lot of research on this for my 125 gallon.
As far as I can tell, and someone please correct me if I'm wrong, but the difference between pool filter sand and play sand is that the pfs is cleaner, as it is designed to be used with water in a pool where humans will be swimming, while play sand is still clean, but just not as much.
As far as brands, the three I have heard people have most success with is Aqua Quartz from ACE hardware, the house brand of Home Depot, and with Leslie's pool supply pfs.
And pool filter sand is not pool filter sand, color will vary from brand to brand, and maybe even from batch to batch.