I am currently Candida cleansing and have completely stopped my kombucha intake, a difficult venture as it is one of my most favorite things in this world. As I homebrewer you'll notice brown strings floating around as you grow. This is yeast. Most all Candida regimens advise to cut all yeast out of the diet.
As far as sugar:
Most commercially produced boocha has about 2 grams Sugar in it that has not been eaten by the bacteria. You can allow your boocha to get more vinegar like, but realize that if you go too long and starve the bacteria of their food, sugar, and create something so acidic it could hurt your stomach.
I've kept myself distracted by creating new herbal teas while cleansing. I especially love chicory root in my french press with whatever herbs I'm feeling for the day.