Fish are a great food source, although not as good as meat. Fish are often the best food for new players, as they are easy to catch and fill up quite a lot of the hunger bar, depending on the fish. They are obtained through the Fishing skill.
To catch a fish, you need a tool to catch the fish with and a spot where there is fish. Fish can be caught with clubs, spears (e.g. javelins, actual spear, staffs, Tridents) and fishing rods, in order of worst to best.
In the current version 3.14 all fish have a value of 0.75, no matter how big/small the fish is. If you want to sell fish, keep the small fish for trading and eat the big fish.
Types of FishEdit
Fish can be broadly divided into 'small' fish (weight =< 1 lb), which give little nutrition, and 'large' fish, 3 lbs and up. Small fish are best used as emergency food sources, trap bait, or ritual offerings, while large fish are good to eat.
Alternatively, small fish make great snacks to stave off early signs of hunger before proper food is available. Cooked perches and breams are decent food for hungry players.
Small fish often make up most of the diet of a fisherman, being caught in large quantities even with just a rod. The smallest fish are not worth smoking or drying, but the bigger fish (anything bigger than a roach) in this category are perfectly suitable for long term preservation.
Often freshwater, they are the easiest fish to catch.
Large fish convert their nutrient-to-fullness ratio somewhat poorly when smoked or dried. A single roasted salmon can comfortably feed a player for two days while a dried or smoked one will often be finished in a single sitting even when not particularly hungry.
These fish make wonderful sources of food, though they can sometimes be hard to find. Fishing in deep water or in rapid tiles makes you more likely to catch one.