Well, I can assure you want to do it will likely not be successful. A 600 watt lamp will give off 2500 BTUs of heat. Before you start, run your light in that closet, and close the door, and wait for a few hours and check what temperature your closet will be. I would suspect it will be well over 90F.... and a fan inside is just going move that hot air around in the space. Plants need fresh temperate air, and without proper ventilation from you, they will not get it. You will need fresh air coming in, and an exhaust so the hot air can be removed.
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SpaceNeedle Reviewed by SpaceNeedle on . Advice please, first time growing. :) Alright, here's the deal. Growing space/condition: 2ft x 3ft x 10ft (closet space) Growing: 2 x White Widow feminized Wall: sterilized covered with Panda Film on walls, ceiling, and floor. Duct taped to keep moisture out. Light: 1 x 600W HPS Lamp setup with ballast Rating: 5