Sorry brother didn't realize you were in the height of summer, can i just ask why you are running your extraction for seedlings mate, if it's a powerful unit it will take out all of the air as you say every hour so could be fighting a loosing battle here try switching it off for a day or two see what happens with your Rh mate, i didn't run mine until two weeks after 12/12 flip and had no problems at all, all the best bro' G'.
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