Mark Peterson III is a green fish that appears in the SpongeBob SquarePants 2 series. He is SpongeBob's friend which SpongeBob finds in Galan City, located near Bikini Bottom. He was born in March 10, 1989. His mother and father took care of him for 25 years, that's until Mark moved out of the house and decided to travel to various cities such as Rock Bottom, Bubbletown, and De Old' Village. In 2018, he visits Bikini Bottom to try out the Krusty Krab. That's where he finds SpongeBob. SpongeBob makes friends with him and that's when the Krusty Krab closed. Mark was quite impressed with SpongeBob's fry cook skills and asked him if he wanted to visit his city. SpongeBob was happy as usual and wanted to go. That's where we see Mark Peterson's blue house. A house with three windows, a chimey, and a dark blue background. 
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