So I've heard both sides..... the fire retardant chemical CAN break down in water and I've heard it can't. WHICH IS IT? Is it safe to use as filtration media or not?I'm currently using it with fish in the pond. Seems fine.... But it's only been a few days and these are just test fish..... Rays will be going into it and I don't really want to risk it if its goin to pose a threat.Any advice from people using this stuff would be great!!!!!!!!!