I've been having very good luck with my kombucha lately. I switched from fruit juice, to using straight up concentrate. I use 100% juice concentrate and my favorite flavors are berry or apple/berry mixtures (apple cherry, apple raspberry, grape, blueberry pomegranate). I make a total of 120 ounces of kombucha a week (3x 32 oz. bottles and 1x24oz bottle) I measure out 1/4 c. juice concentrate for the 24 oz. bottle, then divide the remaining concentrate (from a 12oz. can of frozen concentrate) evenly among the 3 larger bottles. I do CB still in a 1.8 gallon beverage dispenser, but I treat it more like a batch brew (I pull off all my booch at once). I boil a gallon of tap water, then add 1 cup organic sugar and dissolve it, then let it cool for about 30-40 minutes, then add 4 white tea bags and 4 green tea bags and steep them until I remember to take them out (usually an hour or so). Then I let the fresh tea cool to room temp. I pull off my booch from the CB container with my big 4 cup measuring cup and fill my bottles that already have the juice concentrate in them, close them up and turn them back and forth to make sure the juice mixes evenly and set them aside in a warm spot in the kitchen. I do my second ferment for 3 days.
For the Cb container, I use my 4 cup measuring cup to pour the fresh tea into the container, but I use a plastic chopstick to wick the tea over to the side of the container and underneath my scoby. My container is hexagonal, so my scoby ends up shaped like a stop sign. I use the chop stick to push one corner down and then the tea follows the chopstick down into the container and ends up under the scoby, so that the scoby can stay floating on top. Currently I have 3 1/4" thick scobies (two are from times I wasn't able to keep them floating, so they sunk and a new one formed). Because it's winter and a bit colder, I keep my whole setup sitting on top of my hot water heater. I have a half-sized water heater that is in my kitchen and is inside a housing that makes up part of my kitchen counter. The top gets slightly warm to the touch from the 120+ degree water being held inside it, so my booch ferments pretty quickly.
I was doing things almost the same, only I was using fresh fruit juice (blending fresh fruit and straining it) and my booch was ending up very, very acidic (burned my throat) and alcoholic (I can tell immediately if I've had alcohol). I let it sit for about 3 months just ignoring it, and when I finally got in there and cleaned it all up and got things going again, my booch has been tangy and pleasantly tart, but very drinkable and no more throat burning, as well as no more alcohol. I'm loving my booch again and enjoy having a couple cups of it every night with dinner instead of my old can of coke zero.