I wouldn't use the regular play sands. The silica will create mass diatom blooms. And, you really don't know what you're getting with those sands. The exception would be Southdown or Yardright sands.
On the other hand, hobby sands are very expensive. But worth the expense IMO. For an adequate DSB, you need at least 5" of sand on the bottom of your tank...and that is a lot of sand. You can get dry hobby sand for the most part, then seed the top layer with live sand. Absolutely, no crushed coral.