400w hps 2x2 scrog bagseed

this is my setup
2x2 cab without the top not screwed in to adjust height
standard 400w hps system from htg.
regular intake fan
currently putting together a diy cooltube.
i also plan on making a diy carbon scrubber but i dont kno how i would do this because the cab is not sealed completely. i plan on buying 2 or 3 computer fans so put inside to get max airflow.
i will be growing 2-4 plants(is this good to start) in organic soil that has no added nutes. when would be the best time to start nutes?(and a good line of nutes)
was also thinking of topping and lst. i dont have too much height although it is adjustable to about 4 feet. i dont want to veg for too long because of the space. i will place the screen about 8" about the soil.
This will be my very first grow so any and all advice/criticism is welcome. Ive done my research but i will need help along the way. when i begin i will post a link to the journal.

this is the 2x2 cab. the top is not connected which helps with alot of things. i can raise the light by placing books at each corner and this also creates more ventilation. as you can see the doors open and the door to the left will have the fan inside while the right will remain open for ventilation during lighting hours. i will b able to open/close the doors when the lights turn on/off.


400 watt hps from htgsupply


2x2 area planing to germinate and plant 6 or 7 plants and hopefully at least 2 are female.


this is the fan blowing in cool air. pretty efficient and helps keeps the temps down


this is the standard hood from htgsupply

 

this is the top of the cab. my hood is connect by 2 hooks the r in the holes. the holes help with ventilation alot.


this is the cab with the fan in one door. the other door is open and the opening on top is for ventialtion.
because this is not sealed it will be hard to keep smells down. i was thinking of putting dryer sheets on the top part to mask it a little. any suggestions or comments?