Chuck makes a gallon at the time with a scoby that’s a little bigger than my palm. He makes a gallon of black tea and puts a cup of sugar in it. When it is ready, the scoby grows about 1/4 large than it started. And how long it takes depends on temperature other environmental factors.
Don’t seal it up. He uses a gallon pickle jar with a piece of muslin rubber-banded over the top. His first batch took longer than subsequent batches. The instructions said it would take 7-21 days, his usually gets 7-10.
When you decant it, it gets fizzier then longer you leave it at room temp. If you refrigerate it right after you bottle it, it won’t have as much carbonation.
He kept kombucha bottles that he had bought with ‘buch in them before he started making his own and just reuses them.
If you need to put it on hold a little while, you can store the scoby in some ‘buch in a container in the fridge.
Once you feel ready to experiment, flavored teas are not recommended, but you can add fruit juices or herbs or a little cayenne when you are decanting.
Chuck’s answer to “How do you know when it’s done?” is “Taste it. It gets less sweet the more done it gets and it’s really according to your taste.” After a week, check it.
And he uses raw sugar, but any sugar will do.