At night, when they are active, they will congregate towards light sources, like lampshades. They will also feed and breed at night, so you'll see them near food sources or breeding areas. You'll most likely see only a few at a time, as you only rarely see drain flies in large numbers at once.
Sources of Drain Flies
They can live most anywhere that water accumulates for a week or more. Common indoor sites include the fine slime layer that develops along the water surface in infrequently used toilet bowls and tanks, in sink or floor drains in basements or garages, or drain pans under refrigerators.
Behavior: Drain flies are most active at night. They are weak flyers that make short hopping flights of a few feet when they are disturbed. Drain flies rest on surfaces with their wings held over their back like a roof. You'll usually find a drain fly close to its breeding ground.
Mix together 1/2 cup of salt, 1/2 cup baking soda and 1 cup of vinegar. Pour the mixture down the drain. Let sit overnight, then flush the drain with hot water in the morning. This should kill all flies and the organic material they've been feeding on.
Drain flies gather, mate, and lay eggs in moisture or standing water. The slimy film that forms in sewers and drains is a favorite breeding spot. Putting off regular cleaning and maintenance of these areas may attract the pests and offer them a place to feed and develop.
What Causes Drain Flies? Drain flies thrive in stagnant and standing water. Common sources include slow or clogged drains, rarely used and unused toilets, refrigerator drain pans, and standing water created by leaking pipes. They typically enter buildings through basements, windows, and drains.
Do Drain Flies Die in Winter. Most fly species cannot survive outside temperatures below 32°F (0°C). They die unless they find a warm and conducive place to overwinter, such as your home. Drain flies are one of the few insects that can tolerate cold weather conditions.
The good news is most drain fly issues can be fixed within about a week with regular cleaning and careful attention.
One common remedy for killing drain flies is using household bleach. This is a very useful and cost-effective manner for getting rid of these little pests with an item you already have around the house.
What Smell Attracts Drain Flies? Drain flies are attracted to the smell of sewage, rotten food, moisture, mildew, and other bacteria. These smells often come from kitchens and bathrooms, where moist organic matter frequently becomes trapped in pipes. Some theories suggest drain flies are attracted to vinegar.
They do not bite, sting, or spread diseases, but their decaying bodies may cause allergic reactions. They can also spread bacteria from trash, decaying vegetables and fruits. Drain flies breed in areas that are moist and have a lot of organic remains, including: Sinks.
These pests live and breed inside your plumbing pipes, feeding on decomposing material and laying eggs within the gelatinous slime that collects along the interior walls of your drain. Adults can be spotted resting on walls and ceilings of the infested areas.
Drain flies are most commonly found in the bathroom, particularly in drains that have stagnant water or grime sitting in the pipes. Therefore, you'll probably find the small flies in the toilet, sink drain or shower.
One of the reasons that these types of critters — drain flies, in particular — are so difficult to get rid of is that they have water-repellant hair all over their bodies. Furthermore, the drain fly larvae are difficult to drown since “they are able to trap air bubbles and remain submerged for a day or more.”
Answer: The drain flies are not coming up from the P-trap. They are traveling inside from outdoors and reproducing in the organic matter that builds up on the walls inside the drain. You should use 4oz of DF5000 drain fly gel in each drain in the infested room every night for a week.
Drain flies gather, mate, and lay eggs in moisture or standing water. The slimy film that forms in sewers and drains is a favorite breeding spot. Inside structures, they are strongly attracted to light and will be found on glass windows, doors, lamps, and indoor lighting.
Baking Soda, Boiling Water & Vinegar
The pour half a cup of bicarb soda down the sink as well, followed by a half cup of white vinegar. Let it settle for a few minutes then poor some more boiling water down the drain. Follows these steps every few days until the drain flies have completely disappeared.
For effective drain fly treatment, use three products: Forid Drain Gel Cleaner, Gentrol IGR Aerosol, and Pyrid. Forid is an organic microbial grease degrader that breaks down organic material and waste, which will eliminate their food sources and their breeding grounds.
Mix 1/2 cup salt, 1/2 cup baking soda and 1 cup of vinegar and then pour the mixture down the drain, leaving it overnight. In the morning, pour boiling hot water down the drain.
Drain flies are typically only found in the summertime or in places with moderate year-round climates. Cold weather kills off more drain flies than any of their predators. If drain flies are able to find a home indoors, they can continue their development throughout the year, even during the winter.
Learn the Pest Biology
Life Cycle: Adult females lay 30–100 eggs in sludge around sewage and drainage areas. Eggs hatch in 32–48 hours, larval stage lasts 8–24 days, pupal stage 20–40 hours. Adults live about two weeks.
They will not bite you, they are not aggressive, they do not even really stray to far from the breeding source. However, drain flies can indirectly affect your health and family. That decomposing organic matter, sewage, bacteria, microorganisms, and fungi, we spoke about earlier, can host some nasty organisms.
Life Cycle of the Drain Fly
Three weeks. That is all the time the drain fly has to live, and yet they make good use of that time in terms of reproduction. In a typical drain fly litter there are between 30 and 100 eggs, each of which are laid in shallow water and can hatch in as little as three days.
Live drain flies prove to be very resilient to the various water threats they encounter. Droplets impacting drain flies exhibit rapid lateral spreading, retraction, and even rebound, similar to impact on other superhydrophobic surfaces.