Some people are not familiar with the differences between the different fish that are available. They usually assume that all fish are the same, but this is not true. Fish have different types of meat. Some of them may be flaky when cooked while there are also others that can remain intact even with intense heat. The Pollock and codfish are not the same.
The cod is known to have meat that is not very firm so it can be soft when cooked. The Pollock is very soft that you would feel like the flesh is already melting in your mouth. The two can be interchanged with each other when you are following a recipe, but you should know that they are not the same.