Pool filter sand is much more denser than the play sand. It doesnt kick up any dust or fly away in the tank. It settles to the bottom quickly. Whereas the play sand will fly up and will cause dust in your tank. Also hear that the play sand can get into your filter system too.
I would keep up the search for pool filter sand tho as it really is the best type to use. I just love it in my new tank, even the BRs have on occasion rubbed their tummies across it, haha, it must feel good to them. Your bottom dwellers would love it too. Check out garden centers as well as some larger hardware stores that carry garden and pool items. I had to go through a lot of phone numbers in the yellow pages til I finally found some.
Good luck... and just my opinion, but I wouldnt use the play sand ... you may not be happy with it in the end and on another note, you dont have to rinse out the pool filter sand either.
