A rainbow fish is a food item that heals 11 hitpoints when eaten. It can be obtained by cooking a raw rainbow fish on a range or a fire. Doing so requires a Cooking level of 35 and yields 110 Cooking experience if successful. Players stop burning rainbow fish at level 63 Cooking.
Despite the fact that it heals 11 hitpoints, rainbow fish are nowhere near as popular as other fish that heal a similar amount, such as lobsters. The fish is easier to obtain if you are not considering the option of buying food, as this can be fished at the fishing spots near the Barbarian Village, at a lower Fishing level, and faster. This is also close to Edgeville bank. Players must use stripy feathers as bait in order to catch rainbow fish. It is also possible to loot them from gourmet implings.