Heya,
I don't know if anyone posted this before or if this intended/common knowledge but:
You are able to not have fatigue out in the ocean, you can queue up for a pet battle and when you enter and leave the battle your fatigue will be reset so you can swim out further and further into the ocean. I'm not sure if you can make a good use of that but I thought it would be worth posting.
edit: also yes this is my first post, being registered on this site for over 5 years lol.