they are in extreme mode and in story waters mix the to and get big fish.
The monster or named fish in flick fishing do not have to caught in extreme mode. Although you will need a golden charm form the old man in the lighthouse to catch them. So you will have to finish all his quest first to catch them. There is at least one special fish in each location just make sure oyu have the right bait
just keep at it
In the lumbridge castle can't you fish for bonito in flick fishing
Bazzacuda
After completing the lighthouse requests, you receive a golden charm that helps you with the monster fish, so complete the quest first
Cast 30ft. With bait fish.
Just try different bait
You catch bigger fish
You keep fishing in old pond and keep using bait fish
ok first you need a harpoon and a rope too go to the fishing guild and use rope on fishing spot then use harpoon on the fishing spot too and there you after 2mins or more you get it.
win a fish race and you will get new gizmos
Go to waves of doom and use bait fish
Just tap the cast button so it's at about 19 feet and use bait fish. Fish at the old pond.