I am in the process of building a new home for my son's White's tf, and I am using expanding foam on the back of the tank, covered with a mixture of weldbond, coconut fiber, and peat moss. It looks great, but feels a little rough. Is this going to hurt Whitey (ya, I know, but my son named him)? Can I coat it with something to glaze it over a little? I think this is the advantage to the Black Jungle method of silicone plus coconut fiber: it's softer.