The temp of the room will affect the kombucha, obviously, but it's the temperature of the tea that determines how well it ferments. I've seen numbers thrown around from the mid 60 degrees to high 80 degrees Farenheight. Somewhere within that range is best for the colony. Any higher than 100 degrees and the critters start to die. Hence why you cool the batch down before putting the scoby in.

If you really need to monitor the temp of the tea, you can get a flat temperature stick at a pet store for fish tanks and adhere it to your fermenting jar.

I ended up putting a baker's cooling rack over the terrarium heating pad and putting the glass jars on that. Having some air between made the tea warm but not overly so, a cosy fermenting corner in my otherwise chilly kitchen.

That being said, I have to disclose, I haven't brewed any kombucha this winter. I kept letting it ferment too long and it was too sour to drink. I'm trying to psych myself up to trying it again and pulling it after 6 to 8 days.

Anhata
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