I keep all my batches in my basement out of "direct" light. As you mentioned direct sunlight screws with the hops causing them to "skunk". Minor ambient light in the area of the carboy shouldn't be much of concern. I keep mine like I said in my basement, but its not 100% pitch black. Light filters in from the blinds.
To be on the safe side I would cover it up, you can use anything, a x-large tshirt, cardboard box. I have yet to have ambient light hurt anything, but since its upstairs where I am sure its brighter then my basement I would just cover it with something light weight to not contribute to temp rise.
- Irish Red
- Apple Bee Cider
- Orange Blossom Mead
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