I have 3 carbon filters going, and it does a good job. I can only barely detect it when walking in the basement after leaving the house for a few hours…and usually only if skunkier stuff in later flower. I replace carbon filters every 2 years or so. Due for a replacement on the flower tent one soon…next harvest I’ll get around to it.
If no filters…you can smell veg plants in a basement.
I had 2 cats (1 currently) and it REALLY helps litterbox smell (even if you clean it constantly it’s got a smell and I’m fanatically clean).
Kinda thinking about getting an ozone generator again soon and running it 15 minutes a few times a day. Shit works soooo well. Zero smell is ideal for my purposes.