RuneScape Classic Wiki
RuneScape Classic Wiki
The main RuneScape Wiki has an article on: Raw cod
The Old School RuneScape Wiki also has an article on Raw cod.

Raw cod are a type of fish caught from fishing with a big net. They require level 23 fishing to catch. When caught they give 45 fishing experience. They can be cooked to make cod at level 18 cooking, yielding 75 cooking experience, and healing 7 hits when eaten.

These fish can be caught at the following locations: