To pick the right gaff, consider length and hook size. A longer gaff up to 8 feet long allows you to reach out and snare a fish farther from the boat, but it is more difficult to control and aim the hook. An average size is four to five feet long to reach over the side of a boat and snag the target. Short gaffs are handy for moving fish around the boat and handling toothy fish. Match the hook size to the size of the fish. A good all-around model has a three-inch hook. Hooks over four inches are reserved for big fish over 100 pounds.