I don't use CO2 gas so sorry if you're dependant on using that but I live in an apt as well and I used bubble water. Carbonated water like club soda I just mist before lights out. I even know people that use both but I'm not exactly sure on the comparison but I do know the plants can absorb the co2 from the bubble water..
Btw, you won't hermie a plant by doing this
just givin you a hard time hehe. Happy growin!!