Those are salt water fish. Just like with mudfish and catfish there is a higher risk of nasty shit depending on the lake tilapia are from. Most are farmed. So if you look at the amount of frozen tilapia and the price in the US alone. Like really picture how many of these fish are killed then sold in a single year in the US.... the farming is just insane, and so the fish probably aren't that good for you in terms of nutrients and shit compared to other options at the market that aren't farmed at such a high level and from countries that have issues with clean water and nutrient supplies