Other Answers (4)Rated Highest
I tried the glass with vinegar and a drop of dishwashing soap and it really does work. It works better if you put it where you see the most of them.
Purchase a small aerosol can, which will kill fleas as well as gnats. Follow the directions on the can to the letter. You can "bomb" your place and solve the problem easily and safely. Visit Home Depot or OSH and check which products they have. Hope this helps.
spray vinegar on them with a spray bottle. seriously
Going after the source of the gnats will get rid of the gnats.
They are laying their eggs some where.
Some soapy water in a container with a drop of vinegar will attract the gnats and drown them.
They might be laying their eggs in plant soil.
In an old potato or onion.
In the commode tank.