In this episode, Malachi explores the vastness of the oceans! Or at least part of it as Malachi plans to tell us more about it in future episodes. Ben also learns a lot about waves and currents. 

Email: unschooled.malachi@gmail.com
Here is a link to the book referred to in the episode: https://www.goodreads.com/book/show/548695.Tracking_Trash.
And you can find a picture of the frog fish on wikipedia: https://en.wikipedia.org/wiki/Sargassum_fish.