Start with rod and bait
A better rod and stronger bait raise the starting power. Fishing Potion adds 15. Rain, cloud cover, time of day and moon phase then change the result; the same equipment can perform differently across the day.
Check the pond
A small pond reduces fishing power. Ordinary water needs 300 connected liquid tiles for the full pond bonus away from high-altitude exceptions. Honey counts as 1.5 times its physical liquid tiles. A pond below 75 effective tiles cannot produce a catch.
Choose the catch you need
Crate Potion raises the crate roll from 10% to 25%. It does not replace the rod, bait or pond checks. Set your actual liquid and conditions in the fishing calculator before comparing equipment.