Okay, everyone always wants to know how to use sand properely. Myself having need to add more sand and a digital camera handy, I decided to shoot a few pics to help everyone out.
First off, I purchased two 50-lb. bags at $5.92 each from Home Depot. The sand's stock number is 098444200209 at my Home Depot (in Virginia). I've included it in case it's the same throughout Home Depot's range.
The photo on the right is a closeup of the brand, company, phone number and address. Foster Dixiana Filter Sand P.O. BOX 2005 Columbia, SC 29202 (803) 794-2872. Perhaps you can order direct from them, but doubtful.