Paint and sealer question?

I'm planning on building my own hide/rockwall combo and was wondering what kind of sealant I should use? All the Tutorials I've found say "Seal that bad boy" but don't say what kind to use haha. I'm assuming acrylic paint but I wanted to confirm that as well. Thanks!

I have read that some people use modge podge to seal their creations. If the paint is non-toxic and safe for food or children, it will work. Kyrlon spray paint is non-toxic, according to their website.