as several know, I'm building a layout with Styrofoam insulation as my subroadbed, on a door. I was thinking of using the Woodland Scenics 'EZ-Water', which are crystals you melt on a stove, then pour. My question is: How will this affect the styrofoam? I'm planning to dig a channel in the foam and pour the 'water' in. I'm worried the hot 'EZ Water' will melt the foam though.