You never posted an update on this wine, how did it turn out.
I'm a little confused because 1/2 tablespoon is about 1. 5 teaspoons, so for 6 gallons a little less than 1 tablespoon should be fine 1/2 tsp per gallon of about 3 teaspoons per 6 gallons or about 1 tablespoon.
how was it overall.