Crayola sand

the color washes off, turns your water whatever color the sand is, also the color comes off on your hands, the mfg claims it is non toxic.
 
Ive called the company before and they said it should be safe after an excessive amount of rinsing, but i wouldnt trust it.
 
If you are interested in using it, why not experiment a little? I wouldn't put it in an established tank, but why not set up an experimental tank?
 
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