I got these blue sticky traps from my garden store, and the guy said that should take care of the gnats, along with the rockwool covers. He said the gnats aren't too tough to get rid of, and there are a lot worse pests to deal with. So, I consider myself lucky. I haven't had too many issues with bugs, and I hope to keep it that way! your cat is keeping an eye out, that's cool. he's going to expect a little smoky kickback for his hard work!
Good to hear gnats can be solved with your fairly easy solution! Yeah, I may make some treats for her with my clippings, or maybe I'll grow some hydroponic cat-nip! Haha, I wonder where I can find a clone.