Most fresh fish will have gills that are bright red or pink, moist, and clean. Gills that appear brownish, slimy, or pale are an immediate red flag. When it comes to buying whole fish, this simple ...

1) Fish kept in ice for over two days are not good. Check the gills; they should be red in fresh fish and pale in spoiled ones. 2) Some may apply chemicals or ice to maintain gill color.