Eco Strong Fruit Fly Drain Gnats & Sewer Flies Treatment, 1 Gallon, 3 Drain Traps

I have a rental house and the tenants were nasty and allowed soap scum/body gunk to accumulate on the bathtub and surround. They also did not clean the toilets. This allowed the flys to lay eggs on the filth. Within a week of using this product in my drains the problem was gone.

The solution works well. Don't expect the insects to disappear after a single use. I pour it in the drains every evening and, after a few days, the fruit flies will disappear. The sticky pads that came with it were useless. Pro tips: 1. Pour it in every drain. Even in the dishwasher and bathroom sink! 2. Shake the bottle well before pouring. 3. There is a "cleaning product" smell associated with this product. Nothing overwhelming, but it is good to know before buying it.