Optical Illusion - are those turtles in your pool?

How about having a sea turtle in your swimming pool! With the help of these optical illusion applications, you can! You can have a shark, a turtle, or just fish, painted into the bottom of your pool, but what really sells the illusion is that the shadows are part of the adhesive application so it looks like they are floating and not just pretty decoration.

Obviously, a shark would be super-cool. Post your best idea of what else you could paint in the pool!