Look At The Eyes
The most easiest way to tell whether the fish is fresh are to look at the eyes. Fish with bright and clear eyes, with a firm texture indicates that it is fresh. However, if the fish eyes are cloudy and wrinkly, it indicates that the fish isn’t fresh and has been there for quite some time.
Check The Gills Colour
Lift the flap on either side of the head to get a look at the gills. It should be red. The redder the gills are, the fresher the fish. Avoid buying fish gills that look brownish or greyish.
Feel The Stomach
A fresh fish have a firm stomach. Avoid buying if the stomach feels soft or no longer hold its shape or if the insides are starting to split out.
A fresh fish should not smell but should have a mild scent. Avoid buying fish if it has a strong, fish odour or a sour smell. The smell of the fish can be traced back to where it originates from the river or sea where it has been caught. Fresh fish smells natural or pleasant. However, not fresh fish has a pungent and sharp smell of trimethylamine (organic compound released from rotting fish)