Kuala Lampur, April 7 -- Ever wonder where the fish on your grill or in your sushi roll comes from? There's a good chance it was farmed, not wild-caught.

Aquaculture, or fish farming, is the world's fastest-growing food sector, quietly supplying more than half of all the fish we eat.

It's touted as a sustainable solution to overfished oceans and a growing global appetite for protein. But a recent study from researchers in Latvia pulls back the curtain on this booming industry, revealing that freshwater fish farming is swimming against a powerful current of challenges.

Think of it less as a simple pond with fish, and more like running a high-tech farm while navigating a maze of red tape, environmental booby traps, and financial potholes...