it depends on the quality of your current diet. some pescatarians eat dairy and others don't. if you don't eat dairy vitamin d and calcium are of concern. even if you do eat dairy it is likely you need vitamin d unless you are having fatty fish every day. you don't have to worry about omega-3 (dha and epa) if you are having fatty fish twice a week. you need to be sure you are getting enough iron and zinc but with careful planning it shouldn't be a problem. in short a well-balanced pescatarian diet can supply most of the nutrients you need (except d which is low in food). this article can help you make the right choices. of course you can always take a multivitamin if you feel you diet is inadequate.
are there any specific supplements or vitamins needed to be taken for a pescatarian diet?