Yea, Northern lights is about as low odour as you can get.
Celtic Stone although a great plant, does stink.
I had mine up to their 3rd week in flower, and it stunk the house out.
Carbon filters, do just that they filter the odour. They can play up in high humidity areas.
I used to use ozone and it KILLS the smell. but if used wrong, can make a smell of its own.