There are many variables when smoking fish. The thickness of the meat, the type of wood used for smoking, and desired level of smokiness can all change how long it takes for the fish to fully cook. Generally speaking, thicker cuts will take longer than thinner cuts to properly smoke. Depending on the type of pellet grill being utilized, it may take anywhere from 3 to 4 hours for fish to fully cook. Follow the provided instructions for perfect results.