Spectrum / filter questions.

Hi!

I'll start by writing some basic info about myself:

*Know electronics very well
*Soldered ALOT
*Handy, made LED devices for my Venus flytraps/Sundew plants
*Somewhat good with plants (not with weed yet though).

So here's my project:

I will be making a stealthbox for 1-3plants , fit for a closet. And im a supernewbie regarding odours/other cannabis stuff.

I've found some Carbon filters at a local shop, they are really cheap (7bucks each). Do you think theese will work good enough to remove smell from 1-3 plants?

* if not, are they stackable? (many layers for better performance?).
* Do i need to change them every now and then ?

To the next issue:

Im not quite sure yet but i think im a sativa person so i'd love to make a sativa plant. Im very easily affected by thc so a big plant will not be needed (won't sell, only personal use) So what i want is a rather small compact plant, how can i manipulate a plant into growing like this ? Can this be manipulated by spectrum?

*And what ratios/NM are best for a 3-band LED DIY lamp (approx 200w)?


Very grateful for all answers.

best regards.