On a jaunt to PetSmart last week to "socialize" new pup Ollie, I took a stroll down the aisle for fish and reptiles. I saw bags of what appeared to be some kind of calcium sand. And unfortunately I can't remember the name of it now. It seemed to be for lizard tanks and came in an assortment of colors (including plain white). I use crushed coral with some of the mexi-pings and I was wondering if this sand would be good...being not so chunky. Has anyone seen this stuff or tried using it with pings?