A dip into the local knowledge pool

[Matt]

Almost all commercial sand is silicate. Silicates grow diatoms. Diatoms are ugly. Therefore, don't use silicate sand in a reef aquarium. I'd also worry about what else was in "commercial grade" sandbox sand. Tons of things that wouldn't worry a kid will be bad for a reef.

[IceTurf]

its not like i'm just dumping in the sand, i'll rinse it out, plus if there is a problem my filter should be able to take care of it