Foam rock wall epoxy

[kalgra]

Has anyone here built there own faux rock wall and if so did you you epoxy to seal it, was the epoxy FDA approved? I'm trying to find some sort of two part epoxy I can brush onto styrofoam that is both non toxic after curing and also a non solvent so it doesn't melt the styrofoam.

I have spoken to several manufactures about there products but none can guarantee that their product wont leach toxins into the water. What have others used and can it be purchased locally? Where?

Thanks!