Hello, My name is Dr. Kathryn Dench (MA VetMB), Chief Scientific Advisor at Paw Origins (https://paworigins.com/) based in Chicago IL. I'm a holistic & integrative veterinarian from Cambridge University and a Member of the Royal College of Veterinary Surgeons. My veterinary experience and opinions have been widely quoted in Forbes, National Geographic, Reader's Digest, Rover, and VetStreet - notable and reputable publications. From both a veterinary and a practical household perspective, the most reliable, pet-safe method I've found for eliminating fungus gnats is a combined approach of bottom-watering and BTI (Bacillus thuringiensis israelensis) drenches. On their own, quick fixes rarely work; fungus gnats persist because their larvae live in the top layer of moist soil, not because of the adults you see flying around. Bottom-watering is the first key step. By allowing plants to take up water from below, the top 2-3 cm of soil dries out. This directly disrupts the gnat breeding environment. In real terms, when clients or colleagues tell me they've "tried everything," it's usually because they're still watering from the top and unintentionally sustaining the problem. The second step is BTI, typically sold as mosquito dunks or granules. BTI targets gnat larvae specifically and has an excellent safety profile around pets. I recommend dissolving a small amount in water and using it for watering over several weeks. In practice, one application rarely solves the issue. Consistency matters because you're breaking a life cycle, not killing a single generation. In my own home and in homes with pets that I advise, this routine reliably clears infestations within 2-4 weeks, without resorting to insecticides that could pose risks to cats, dogs, or curious children. As a vet, that safety margin is non-negotiable. I generally don't recommend sand topdressing in pet households. While it can reduce egg-laying, it's inconsistent across pot types and can create compaction or drainage issues, and inquisitive pets may dig or ingest it. The bottom-watering + BTI routine is simpler, repeatable, and far more reliable. I hope this helps for your piece; please feel free to reach out if you have any further queries. Kind regards, Dr. Kathryn Dench MA VetMB MRCVS Chief Scientific Advisor, Paw Origins Link to bio for article: https://paworigins.com/blogs/vet-blogs/about-dr-kathryn-dench-ma-vetmb