I'm on my third batch ever, currently undergoing F1. My last batch was incredibly fizzy, even just out of F1, and I suspect some of that carbonation made it into the starter tea I saved for this batch. Point is, my SCOBY has now floated all the way to the top, so only the bottom layer touches the tea. It's slowly starting to balloon up a bit, and I'm worried this will inhibit the growth of a new SCOBY. I haven't touched it at all yet; when should I intervene, if at all?