the seawater and fresh water is a big difference.
The most important difference is that one is the pressure, the other is salinity.
let's talk about pressure.
Scientific research workers and proves that the pressure in the water, far more than the large fresh water, and green for fish and live in 15 ~ 40 meters under the sea water, at the age of the water pressure.
In the long history of green of the fish had to adapt to the huge water pressure of internal and external structures such as cheese, and muscle elastic.
If at the age of live fish in the sea, suddenly arrested leave the surface of the water, is not nearly as air pressure outside the pressure of the water.
Because of the pressure to reduce suddenly, because the pressure of air inside the maw decreases to swell, even more than it accommodate volume would burst.
In addition can also cause a part of the small blood vessels in the body is broken, and stomach out of the mouth, and eyes prominent from the eye socket, and so on.
All of this is to make the green of the fish left the water will soon be dead.