Can a minn kota all terrain 65 lb thrust handle a 20' boat in salt water?

Get the biggest one you can afford and make sure it is hand operated if you fish standing up. Trying to use a trolling motor in rough water with a foot control while standing is a sure way to get thrown overboard. I fish a lot of tidal marsh areas in South Louisiana in a 16� foot boat with a 70# Riptide and wish I had more. With a 20' boat you should try for a 101# it won't be cheap but you will be happier.