Just a simple question
This isn’t really something you need to worry about in fish. Yes, you may find very small amounts in cooked fish but not enough to raise a huge risk alarm.
Id be more concerned with this in regards to eating large amounts of high heat grilled red meat or processed meats.
Epidemiologically, fish consumption is associated with better mortality and morbidity risk.
But yes steaming or low heat cooking methods are ideal for limiting HCA production in any cooked meat product.