When buying fish

News today: "...a fish with cloudy eyes is an indication that it is well past its prime. Your fish should also have bulging eyes. Eyes that are sunken reveal a dehydrated fish, which means it spent more time on ice than in the water before you made your purchase."

Cloudy eyes = cloudy corneas =  corneal edema = dead endothelium

Yep, not fresh enough for people with more sensitive palate.

Fish covered with ice, not on ice, are rarely dehydrated. Those with sunken eyes probably smell too fishy already, they should be avoided indeed.