I was told 2-3 minutes if plants are around.
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MysteryMoogOldschool Member
Well, i have no hard and fast suggestions. I shut all vents down once a week, and turn it on for 3 minutes inside my flower room. Let it sit for 10 minutes, then kick everything back on. Clears out in minutes, if not seconds via vents. I do not know its actual half life time, though i would take a gander at around an hour give or take.