I wouldn't try to set up an AC that is connected directly to the tent unless it is like 8x10. You would be better served to cool the airspace around the outside of the tent, and allow the ventilation system pull the cooled air into the tent. This way you don't get very cold and dry air blowing in directly on the plants. You want to mix that cooled air with warmer and moister air so that you have a nice comfortable air mass going into the tent.
Thank you cause I had that concern aswell. . Looking that my tent is avg sized (4x4x6.5 ft) Altho it will be compact it will still take up spice that can be used. . Im guessing my room is 16ft x 20 feet.. I took measurements whn I had the smell issue and redid the ceiling. . So I'm asking, wht would be the best size or add o been seeing, btu's?
In a 16x20 room I would use no less than 10K BTU AC. The little mobile ac units are not the best for these types of setups because they continually have to exhaust air that is used to cool. They take in air from the room and half is cooled and returned to the room, the other half is heated and expelled. This means that the ac by itself is continuing to pull warmer air in from outside the room. Using a wall mounted unit is better as it is more efficient at cooling.