I'm setting up an aquarium and to protect the bottom I was considering egg crate. However, since some posts suggest that the crate will be exposed by digging, I was wondering if a silicone mat at the bottom would protect the glass and maintain aesthetics? I didn't want to add the mat if it would be dangerous for the fish. I was hopeful that a food grade mat would be safe, even if more expensive than egg crate. Thoughts?