1-Put 2 gal. of water and 2 lbs of baking soda in the tank.
2-Sail hard for 4 hours with lots of pounding to weather on both tacks crossing large tugboat wakes whenever possible.
3-Return to dock and drain tank, flush with fresh water .
4-Add 2 gals of white vinegar ( no Balsamic, Ebb )to empty tank and repeat step 2 & 3.

This makes cleaning fun and a chance to have a drink or 2 if you are so inclined .