Help, Apartment Balcony Closet Grow. Is carbon filter needed?

Hello everyone. I'm growing in my apartment balcony closet which is located on the 3rd floor of a 4 floor complex. Using a 600w MH/HPS light on 1 plant (hoping to make 1 or 2 more clones). The balcony closet, has a vent near the ceiling which directly vents outdoors which i have connected a blower fan to, that provides an exhaust for the heat and smell. The plant is healthy and in it's midway into the vegetative stage about 1 1/2 ft. tall.

Question: How important will it be for me to have a carbon filter/scrubber to filter out the smell?

I would not bother with one plant and seeing as you are three stories up. any smell, which there will be minimal of, will blend in with the air quickly.

You won't have a lot of smell from one plant, but you will have smell. What you have to ask yourself is, will other people smelling it put you in jeopardy. Will the plant's smell entice someone to break in and steal your plant, or maybe make them call the cops (if it's not legal where you are)? If you're in a place where people are generally cool and a little odor is no big deal, you may be able to get away without one. Personally, I'd get one, but I've got that better-safe-than-sorry attitude. You could get away with one of the DIY options mentioned in the odor control thread.

One plant will have min smell if any noticeable to neighbors.