Grow tent setup. 40*40*80 with 50w led? 1 large or 4 small plants? Computer fan for circulation?

Since your area will be a bit large I would recommend at least a 4 inch inline fan with accompanied carbon filter I have a 4x4 tent and I use a 6 inch fan. Sure you pay a bit more but it does a hell of a lot better job than a 4 inch. Also make sure you have some vents at the bottom so you can produce good air flow. As for the light 50 watts will not cut it. In fact when on Amazon buying a light DO NOT TRUST ANY WATTAGE. These are non scientific. What you should look at are the par test charts. The higher the par the more energy will go into the plant and equal a higher yield. You will have to typically spend between 150-400 cdn on a decent light. So do your homework before you buy your light as it will be the most critical investment you will make. The second one being your carbon filter but let's focus on one light at a time. I have two lights running in my tent right now. One is a phillizon light that claims to rate against a 1000 watt hps but in fact only draws 180 watts from the wall and can only really cover 2ft x 2ft. If I were to use this light in my tent my plants would not have decent lighting. My mars hydro 2 900 watt equivalent would however cover my 4x4 but just barely. This is why I still have my phillizon still kicking around. Please feel free to follow my current diary. As for your plant count thing I would recommend going with 4 plants since you are new to the game and training would be a bit advanced for you at this stage. Not to mention training 1 plant to produce a lot takes more time. Just stick with 4 plants in 3 gallon pots and you should be off to the races. https://www.mars-hydro.com/buy-mars-ii-900-full-spectrum-led-grow-light-mars-hydro-for-sale https://www.amazon.ca/gp/product/B075SRHWQP/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

Hi mate I'm normally asking questions on here but I have actually built my own grow box the same size as yours, I would recommend going a bit taller as that has been my only problem. Also order mylar sheeting online it's cheap and very good reflection. A 4 inch computer fan will work perfectly. I also am using a so called 600w ebay light I bought for £23 and its doing a great job. I used a cardboard box 80cm tall and 50 x 50. Good luck!