More Fish In The Sea is the last quest given by the Sea Fisher in the sea fisher's quest line.
Description[]
Deliver a special fish to the Sea Fisher.
— Journal
Walkthrough[]
After you delivered the oil and finished Finding The Flotsam, you can talk to the sea fisher:
More fish in the sea
Catch me a [fish name]. They can be found at [location]. They tend to prefer [lure/bait information].
The Sea Fisher will give you hints on how to catch the fish he ask for (baits, lures, locations). For more information about those fish, see Fisherman Quest Fish.
For each fish delivered, you will be rewarded with a unique item. This process is random and can be repeated infinitely, so it's possible to have multiple duplicate items.