i have never had success with just MG i mix 1/3 perlte 1/3 peat moss and 1/3 MG works geat and the space is tiny but there are eople that grow in hollow pc towers so if you just want to grow then it s good
might want to have 2 fans 1 for venting in air (from the bottom) and 1 venting out air from the top
and i would paint the walls white to increase light reflection foil isnt that good but it is better then nothing
and for nutes plants like nitrogen durring veg and phosphorus durring flowering and they should be added after the roots have settled in generally after 2 weeks
dont start at full dose start at 1/4 dose then work your way up to full doses.
and the best temperature is around 75