lyling,
What you eat, macrobiotically, depends on you and your condition.
If you are a person trying to achieve some kind of healthier state or trying to recover from some kind of problem or sickness, then most of the time you might want to stay away from the more yang forms of seafood like shrimp, prawns, crabs, lobsters, squid, oysters.
Scallops, clams, and mussels, should be okay.
It is recommended by the
Kushi Institute http://www.kushiinstitute.org/whatismacro.html that most macrobiotic people aiming for good health stay away from the more yang animal foods, including the more yang and fatty fish and crustaceans, and choose the more yin fish like " fresh white-meat fish such as flounder, sole, cod, carp, halibut or trout".
If you are really healthy and like to experiment, you could sample a small portion (like a couple of ounces, cooked) of a yang fish like salmon or tuna and see how it affects you.
Jessica Porter in her book
The Hip Chick's Guide to Macrobiotics http://www.cybermacro.com/Macrobioti..._Macrobiotics/ says that "fish should always be balanced with green upward growing vegetables" and that "it's not unusual to serve a lemon wedge, dessert and/or a beer at fish meals as well".
Thank you, very much.
Bruce Paine