When cooking or grilling fish, we all have the tendency to keep checking the underside before making "the flip". That's why a lot of the time bits and pieces of the fish get stuck to the pan or grill. Not making it good eats. Here's a way to make sure you get a nice and perfect fish:
Just leave it alone.
That's it. Don't poke or try to lift it. When the fish is ready, it'll simple just glide onto the flat spatula with ease. A piece of fish that's an inch thick would generally cook for about 4 minutes on each side. So size definitely matters. The thinner the fillet, the quicker it'll cook. But make sure it's on medium to high heat for best results.