The Color of Mermaid Crap.

So here is one for the books. What do you say when your roommate paints the great room a horrible shade of Underwater Adventure Teal? It looks like the little mermaid came in and shat all over my walls. When I walk into the room I start holding my breath, and I pick up the pace to cut through to the kitchen

I lack the part of my brain that screens out inappropriate words, so I know if I say something it will be rude. What's a nice way to tell the roommate that life is not better down where it's wetter? Take it from me...