Wrong, all wrong. The only BEST way to incorporate cooling and dehumidification, and heat (if you purchase a window a/c unit with heating capabilities) for a grow tent, especially when it is located in a garage, is to install a window a/c unit through a window in the garage like normal, and butt the grow tent up to it, cut a square hole in the tent for the front of the window unit to pass though and your done. If the window unit doesn't go deep enough into the tent then slide it forward, it will move in and out of a window 10 or 12 inches which is more then enough to fine tune the fit. Portable a/c units do not work, period! Installing a heat run from a central air conditioning system of a home, and piping it directly into a grow tent does not work, period! Makeshift duct fabrications made to any heating and/or cooling unit that is piped directly into a grow tent does not work, period! Dry ice does not work, period!