http://www.badmanstropicalfish.com/forum/index.php/topic,14552.0.html
hey guys. i just found this thread of someone who used the stuff in their aquarium and hasn't had any issues so far.
After seeing the pix in that link, I think i may use it. I have a 20 gallon that I haven't got around to setting up yet. My wife and I have been wanting to do a glofish tank with it. i think that sand will look nice in that application.