Nemo Darla Aquarium Background by Penn Plax. Recreate the Underwater World of the Finding Nemo Adventure. The adventure starts in the warm tropical waters of the Great Barrier Reef off Australia where a Clownfish (Percula) named Marlin lives with his only son Nemo. Fearful of the ocean and its unpredictable risks, Marlin struggles to protect his son. Nemo, like all young fish is eager to explore the mysterious reef. Pushing his luck a little too far Nemo is unexpectedly taken far from home and ends up in a dentist\'s aquarium. Marlin becomes the hero in an epic journey to find his son during which he encounters many excitements on his way to rescue Nemo from ending up with Darla. Available in two sizes this quality background can be trimmed to size to fit most young persons aquarium.